ARM: dts: stm32: add EXTI interrupt-parent to pinctrl node on stm32mp131

Add interrupt-parent property in pinctrl node to use GPIO as IRQ.
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Signed-off-by: Fabien Dessenne <fabien.dessenne@foss.st.com>
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>

arch/arm/boot/dts/stm32mp131.dtsi

@@ -259,6 +259,8 @@ pinctrl: pinctrl@50002000 {
 			#size-cells = <1>;
 			compatible = "st,stm32mp135-pinctrl";
 			ranges = <0 0x50002000 0x8400>;
+			interrupt-parent = <&exti>;
+			st,syscfg = <&exti 0x60 0xff>;
 			pins-are-numbered;
 
 			gpioa: gpio@50002000 {