arm: stm32: add new architecture for STM32MP family

- add new arch stm32mp for STM32 MPU/Soc based on Cortex A
- support for stm32mp157 SOC
- SPL is used as first boot stage loader
- using driver model for all the drivers, even in SPL
- all security feature are deactivated (ETZC and TZC)
- reused STM32 MCU drivers when it is possible

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index 5881fdc..4fa8b38 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -72,6 +72,7 @@
 machine-$(CONFIG_ARCH_RMOBILE)		+= rmobile
 machine-$(CONFIG_ARCH_ROCKCHIP)		+= rockchip
 machine-$(CONFIG_STM32)			+= stm32
+machine-$(CONFIG_ARCH_STM32MP)		+= stm32mp
 machine-$(CONFIG_TEGRA)			+= tegra
 machine-$(CONFIG_ARCH_UNIPHIER)		+= uniphier
 machine-$(CONFIG_ARCH_ZYNQ)		+= zynq