Add board support for 96Boards STM32 Sensor Mezzanine board. This board
is one of the 96Boards Mezzanine board which can work standalone or on
top of the 96Boards Consumer Edition boards.
Below are some of the key features of this board:
1. STM32F446VE MCU
2. 96Boards high/low-speed connectivity
3. Arduino™ Uno revision 3 and Grove connectivity
4. Integrated MEMS sensors:
1. LSM6DS3H
2. LIS3MDL
3. LPS22HB
4. MP34DT01-M
5. On-board ST-LINK/V2-1 debugger/programmer
More information about this board can be found in the 96Boards product
page: https://www.96boards.org/documentation/mezzanine/stm32/
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>