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/drivers/serial/Kconfig b/drivers/serial/Kconfig
index 76d5e99..eb718a6 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -609,10 +609,10 @@
 
 config STM32_SERIAL
 	bool "STMicroelectronics STM32 SoCs on-chip UART"
-	depends on DM_SERIAL && (STM32F4 || STM32F7 || STM32H7)
+	depends on DM_SERIAL && (STM32F4 || STM32F7 || STM32H7 || ARCH_STM32MP)
 	help
-	  If you have a machine based on a STM32 F4, F7 or H7 SoC you can
-	  enable its onboard serial ports, say Y to this option.
+	  If you have a machine based on a STM32 F4, F7, H7 or MP1 SOC
+	  you can enable its onboard serial ports, say Y to this option.
 	  If unsure, say N.
 
 config ZYNQ_SERIAL