This is an intrim nuttx patch that fixes the missing CONFIG_
prefix on RAMTRON_WRITEWAIT. PR submitted upstream. This will
be in affect until the next uptake of upstream NuttX
STM32F4 does not require the HSI to erase or program FLASH
The HSI needs to be left on until a new clock source is chosen.
(we leave it on all the time)
1) Ensure if CONFIG_SERIAL_DMA is set that cdcacm uart_ops is initalized
with correct functions in correct slots.
This was detected only with PX4 build flags
2) C&P error from F7 would prevent CONFIG_STM32_SERIALBRK_BSDCOMPAT ifdefed
code from being included.
