STM32 SOC updates for v4.12, round 1.

Highlights:
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 - Create a dedicated Kconfig for STM32 machine
 - Add support of STM32H743 MCU
ARM: stm32: Add a new SOC - STM32H743

The STM32H743 is a Cortex-M7 MCU running at 400MHz and containing 1MBytes
internal RAM.

Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
2 files changed