SAM4L:  Re-order some clock initialization.  There was a dependency of GCLK0 on DFLL, but DFLL was being enabled after GCLK0

LPCXpresso-LPC1115:  Add a minimal NSH configuration that has the file system disabled.  Update README with OpenOCD instructions.  From Alan Carvalho de Assis.

LPC11xx: Add support for up_getc() which is needed for NSH if there is no file system.  From Alan Carvalho de Assis.

SAMD/L: Change ordering of some initialization steps to match Atmel sample code.  Add Errate 13134 support.  SAML wait states changed to 1.  Sample code is using 0

Initial support for the NXP LPC11 family and the LPC1115 MCU in particular.  Contributed by Alan Carvalho de Assis.

SAML21 clock config: Fix a misthink in last commit.  Move setting of ONDEMAND to after clock is enabled in most cases

SAML21: Add logic to support GLCK peripheral channels; add logic to configure FDPLL lock timer and ref clock GCLKs

STM32: Building stm32_rng.c should be conditioned on CONFIG_STM32_RNG, not CONFIG_DEV_RANDOM.  From Juha Niskanen

SAM3/4 Serial:  In NONBLOCKING mode serial does not receive bytes from UART.  This happens because RX interrupt was disabled in the setup routine.  To fix this I save interrupt configuration before uart shutdown and restore it after.  From Max Neklyudov.

SAML21-Xplained:  Update the cloned SAMD20-Xplained board configuration for specifics of the SAML21-Xplained