wireless/bluetooth:  Soften use of enter_critical_sectino() which is a performance hog in SMP configurations.  Replace with spin_lock_irqsave() in most cases.  That is the same for single core CPUs, but much more efficient in SMP configurations.  And better, repace with sched_lock() if there is really no necessity to disable interrupts too.

tools/mkromfsimg.sh:  Include an option in mkromfsimg.sh to ignore FAT/RAMDISK. This permits you to build tiny systems with ROMFS but with the rather large FAT FS support.

fs/mount:  Fix wrong size reported by df -h.  Reason is that size in bytes is calculated always on uint32_t types and cards bigger than 4GB will overflow uint32_t type. Solution is to use uint64_t where possible.

wireless/bluetooth:  Use nxsem_timedwait() vs nxsem_wait() when waiting for response from the HCI device.  Adding this timeout prevents things from hanging when there is a problem with the connect HCI UART (in the current test, when there is no HCI UART connected).

wireless/bluetooth and drivers/wireless/bluetooth:  Simply the driver registration/initialization interface.

arch/arm/src/stm32:  In HCI UART driver, need to disable Tx interrupts after frame sent.  Otherwise, we get infinite Tx interrupts.

Various fixes/changes from intial testing of the HCI UART on the STM32F4-Discovery board.  Re-organized how the Blutetooth network driver is initialized.  Added lots of new debug output.  Add a new STM32 F4 Discovery configuration for testing the HCI UART.  Various fixes to get through initialization (still does not).

fs/smartfs:  Fix a hardfault in SmartFS.  Problem occurred when opening a file with O_CREAT (only) when the file arelready exists but has a size of zero.

configs/stm32fdiscovery:  Add support in bringup logic to initialize the HCI UART and register the HCI UART network device.

configs/imxrt1050-evk:  This commit adds support for booting from the on board HYPER Flash. I placed the boot and flash files in the /configs/imxrt1050-evk/ , because I thing they are board related, so for other board or other flash this files has to be changed.  So far I verified that the __start function is called and the code is executing from flash, but still the rest of the code is not tested.

Squashed commit of the following:

    arch/arm/src/stm32:  Add Kconfig options needed by the HCI UART.  Various fixes to finally get a clean error free compile with no unexpected warnings.
    arch/arm/src/stm32:  In HCI UART, use spin_lock_irqsave() instead of enter_critical_section() whenever possible.
    arch/arm/src/stm32:  In HCI UART, fix up naming of configurations so that they are unique.  Still needs Kconfig settings.  Modify logic so that there can be multiple HCI UARTs, some supporting DMA and some not.
    arch/arm/src/stm32:  Integrate watermarks and software Rx flow control into the HCI UART driver.
    arch/arm/src/stm32:  Eliminate some HCI UART UART configuration options.  Per the HCI UART spec, the link will b 8 data bits, no parity, 1 stop bit... Always.
    arch/arm/src/stm32:  Trivial cleanup
    arch/arm/src/stm32:  Fixes most initial compilation issues STM32 HCI UART driver.  Still need to set up USART configuration parmeters for HCI UART
    arch/arm/src/stm32:  Completes first cut at STM32 HCI UART driver.
    arch/arm/src/stm32:  Completes most of read logic for HCI UART.  Still needs to be able to block if no read data is available.  Still missing write and flush logic.
    drivers/wireless:    Remove txenable from HCI UART methods.  arch/arm/src/stm32:  Reorganize some structures in HCI UART.
    arch/arm/src/stm32:  Still messaging the HCI uart driver.
    arch/arm/src/stm32:  Some trivial renaming.
    arch/arm/src/stm32:  A little more HCI-UART logic.
    arch/arm/src/stm32:  Initial setup to support HCI-UART.  Little more than the serial driver with some name changes and a few things removed.

net/sixlowpan:  Fix a constant value used in IPv6 address decompression.  The 0x0200 value used in the address modification should be in network order.

Change ordering of round-robin time slice check (sched_process_scheduler()) and processing of wdog timers (wd_timer()).  wd_timer()'s callback function can change current running task and, hence, must be done after the time slice check.

The time slice check will decrement the currently running task's time slice allotment.  If such a context switch occurs, then the newly started task will lost one could of that allotment before it even has a chance to run.

This commit brings in basic support fo the i.MX RT 1050 'crossover' SoC.  The basic support is complete and compiles without error, but is still untested.

This port was the joing effort of Janne Rosberg, Ivan Ucherdzhiev, and myself.  I give credit to Ivan for the kill because he is the one to held on to the end.

Squashed commit of the following:

  Author: Gregory Nutt <gnutt@nuttx.org>
    configs/imxrt1050-evk/scripts:  Add section to linker script to handle the case where RAMFUNCs are enabled.  RAMFUNCs appear to be enabled in the default configuration ... they probably should not be enabled.

  Author: Ivan Ucherdzhiev <ivanucherdjiev@gmail.com>
    arch/arm/src/imxrt:  imxrt_lowputc.c is finished. Now everything needed for the initial port is done and ready for testing.
    arch/arm/src/imxrt:  Add logic to imxrt_lowputc.c.  Still incomplete.

  Author: Ivan Ucherdzhiev <ivanucherdjiev@gmail.com>
    arch/arm/src/imxrt:  Add serial support.  configs/imxrt1050-evk:  Add linker script.

  Author: Gregory Nutt <gnutt@nuttx.org>
    arch/arm/src/imxrt:  Add initial cut at imxrt_allocateheap.c

  Author: Ivan Ucherdzhiev <ivanucherdjiev@gmail.com>
    arm/arm/src/imxrt:  Completes all definitions for PADMUX, CTLMUX, and IOMUX_INPUT and mapping tables on imxrt_gpio.c and imxr_iomuxc.c.
    arch/arm/src/imxrt/chip:  Add definitions for IMXRT_PADCTL and IMXRT_PADMUX registers.  Only the IMXRT_INPUT definitions in this commit.
    arch/arm/src/imxrt/chip:  Add more IOMUXC register definitions.

  Author: Gregory Nutt <gnutt@nuttx.org>
    configs/imxrt1050-evk:  Add STRIP definition to Make.defs.
    arch/arm/src/imxrt:  Bring in i.MX6 memory configuration settings.
    arch/arm/src/imxrt:  Remove call to non-existent imxrt_gpioinit() from imxrt_start.c.
    arch/arm/src/imxrt:  Bring in incomplete imxrt_iomuxc.c file from i.mx6.
    arch/arm/src/imxrt:  Add first cut at GPIO interrupt logic.
    arch/arm/include:  Add definitions to support a second level of GPIO pin interrupts.

  Author: Janne Rosberg <janne.rosberg@offcode.fi>
    arch/arm/src/imxrt:  Add imxrt_wdog.c/.h

  Author: Gregory Nutt <gnutt@nuttx.org>
    arch/arm/src/imxrt:  Port SAMv7 interrupt logic to imxrt_irq.c.
    arch/arm/src/imxrt:  More clarification of the start-up memory map.
    arch/arm/src/imxrt:  Some mostly cosmetic clean-up to the imxrt_start.c file that was so rudely taken from the SAMv7.
    arch/arm/src/imxrt:  Add imxrt_start.c.  Initial commit is the the SAMv7 startup logic with name changes.

  Author: Ivan Ucherdzhiev <ivanucherdjiev@gmail.com>
    arch/arm/src/imxrt:  Adds a few IOMUXC register definitions.

  Author: Janne Rosberg <janne.rosberg@offcode.fi>
    arch/arm/src/imxrt:  Add imxrt_clockconfig.c/.h
    configs/imxrt1050-evk:  Add clock configuration definitions to board.h
    arch/arm/src/imxrt:  Fix CCM register name; Fix doubly defined in LPUART bit field.
    arch/arm/src/imxrt:  Add analog defines to CCM register definition header file.

  Author: Gregory Nutt <gnutt@nuttx.org>
    arch/arm/src/imxrt:  Bring in GPIO C files from i.MX6.  Things are in disarray now because that GPIO logic depends on IOMUXC logic which is not yet in place.
    arch/arm/src/imxrt:  Add a few more GPIO definitions to make the header file compatible with i.MX6
    arch/arm/src/imxrt/chip:  Add GPIO register definition file.

  Author: Janne Rosberg <janne.rosberg@offcode.fi>
    arch/arm/src/imxrt:  Add DCDC register definitions.
    arch/arm/srch/imxrt: Add CCM register bit definitions

  Author: Gregory Nutt <gnutt@nuttx.org>
    Purely cosmetic
    arch/arm/src/imxrt:  Add system reset controller register definition header file.
    Embarassingly trivial change left in compiler.
    arch/arm/src/imxrt:  Finishes i.MX RT1050 LPUART register definition header file.
    arch/arm/src/imxrt:  Beginning of an i.MX RT1050 LPUART register definition header file.
    Some trivial things

  Author: Janne Rosberg <janne.rosberg@offcode.fi>
    arch/arm/src/imxrt:  Add imxrt_wdog.h
    arch/arm/src/imxrt:  Add initial imxrt_ccm.h

  Author: Gregory Nutt <gnutt@nuttx.org>
    Trivial update to README.
    arch/arm/src/imxrt:  The i.MX Rt implements 4 bits of interrupt priority, not two.  Thanks, Janne.
    arch/arm/src/imxrt:  Fix some initial compile issues.  Still a long way from complete, but there is a buildable environment now for the imxrt1050-evk.
    configs/imxrt1050-evk:  Add an initial NSH configuration for testing.
    configs/Kconfig:  Hook the i.MX RT 1050 board configuration into the NuttX configuration system.
    configs/imxrt_evk:  Add the framework for i.MX RT 1050 board support.
    arch/arm/src/imxrt:  Bring in a few more files from LPC54xxx.
    arch/arm/src/imxrt:  Bring in imxrt_clrpend() from the LPC54xxx.
    arch/arm/src/imxrt:  Bring in Cortex-M7 SysTick setup from the SAMv7.
    arch/arm/src/imxrt:  Add a few easy files.
    arch/arm/src/imxrt/chip:  Add memory map header files.
    arch/arm/src/imxrt:  A few basic files to start the port to the i.MX RT 1050.

include/nuttx/wireless.h:  Fix some coding standard violations.  configs/indium-f7:  Fix some compile errors found in build testing.

arch/arm/src/:  Problem: stm32f30xx hangs waiting for LSE to initialize.  Reason for hang is that operation of setting LSE_ON does not take effect because there is no clock on PWR peripheral.  this is initialized later in the code

Remove all support for the CC3200 and CC3200-Launchpad.  This was a port that was started but never completed.  What good is partial CC3200-Launchpad board support with no wireless support?

Squashed commit of the following:

    Remove final references to CC3200 from the repository.
    arch/arm/include/tiva:  Remove all CC3200 support.
    arch/arm/src/tiva:  Remove all CC3200 support.
    configs/cc3200-launchpad:  Remove the board support directory.

drivers/sensors/max31855: Add multiple max31855 sensors feature and support for bambino-200e and stm32f4discovery

add generic upper-half motor driver

Approved-by: Gregory Nutt <gnutt@nuttx.org>

Squashed merge of the following:

Author: Gregory Nutt <gnutt@nuttx.org>
    drivers/sensors:  Fix some minor typos in last commit that cause some compile problems.
    drivers/sensors/:  Clean up some coding standard isses in LM330 and ADXL372 drivers.
    drivers/sensors/README.txt:  Clean up some long lines and odd line breaks.
    include/nuttx/sensors:  Completes coding style review of adxl372.h, cluster_driver.h, and lsm330.h.

Author: Bob Feretich <bob.feretich@rafresearch.com>
    Add LSM330 SPI and ADXL372 drivers along with the cluster driver infrastructure.

fix warnings found in stm32f334-disco/buckboost configuration

Approved-by: Gregory Nutt <gnutt@nuttx.org>

drivers/bluetooth:  Extend device simulation.  Now makes it all the way through initialization without error.  wireless/bluetooth: Add support for IOCTL commangs to get BR/EDR and LE features.

Bluetooth:  Better integrate NuttX Bluetooth IOCTL commands and NetBSD IOCTL commands.  Stanardize naming.