fs/hostfs: Add a special file system for use with simulator that supports access to the host file system from the simulation.  From Ken Petit

size_t should be 64-bits on a 64-bit machine. mmsize_t should be 32-bits (unless CONFIG_MM_SMALL is selected).  This commit backs out the last change to stddef.h

Revert "Add option to specify logical sector size during low level format plus adds some run-time geometry tests.  fs/smartfs: Remove the 'mksmartfs()' code from the kernel 'fs'"

This reverts commit 96faf0fa3251ca10a17daddc728d931be5a206e0.

Add option to specify logical sector size during low level format plus adds some run-time geometry tests.  fs/smartfs: Remove the 'mksmartfs()' code from the kernel 'fs'
  directory and build.

open() has been extended.  You can now open block drivers and access them just as you can character drivers.  For example, you can hexdump a block device.

drivers/mtd/smart.c  Fixed SmartFS wear level error that occurs when the logical sector size is too small to save all wear level status bytes in a single sector.  Logical sectors 1 and 2 were simply not being allocated and then the read_sector and write_sector routines were failing.  From Ken Petit

drivers/mtd/mtd_progmem.c: Add an upper-half driver that can be used with any FLASH library that provides the itnerfaces defined in include/nuttx/progmem.h

CAN: Add a new CAN upper-half interface, can_txready(), that can be used to break deadlock conditions in certain CAN hardware that supports queuing of TX messages