ARM: stm32: Allow build irq-stm32mp-exti driver as module

Drop auto-selecting the driver, so it can be built either as a module or
built-in.

Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240620083115.204362-8-antonio.borneo@foss.st.com

Author: AntonioBorneo

arch/arm/mach-stm32/Kconfig

@@ -11,7 +11,6 @@ menuconfig ARCH_STM32
 	select CLKSRC_STM32
 	select PINCTRL
 	select RESET_CONTROLLER
-	select STM32MP_EXTI if ARCH_MULTI_V7
 	select STM32_EXTI if ARM_SINGLE_ARMV7M
 	select STM32_FIREWALL
 	help