mpconfigboard_common.h now sets the defaults so there is no longer a need
to explicitly list all configuration options in a board's mpconfigboard.h
file.
This is a low-cost evaluation kit board from ST based on the STM32
Nucleo-144 form factor. It uses the STM32F746ZG MCU in the LQFP144
package. The MCU has 1MB of flash and 320kB of System RAM.
Cortex-M7 runs at up to 216MHz.