ARM: dts: stm32: add RTC support on STM32H743

This patch adds support for RTC on STM32H743 SoC.
It also adds dt-bindings/interrupt-controller/irq.h include and uses it to
configure RTC alarm interrupt.
Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Alexandre Torgue <alexandre.torgue@st.com>

arch/arm/boot/dts/stm32h743.dtsi

@@ -44,6 +44,7 @@
 #include "armv7-m.dtsi"
 #include <dt-bindings/clock/stm32h7-clks.h>
 #include <dt-bindings/mfd/stm32h7-rcc.h>
+#include <dt-bindings/interrupt-controller/irq.h>
 
 / {
 	clocks {
@@ -347,6 +348,20 @@ vrefbuf: regulator@58003c00 {
 			status = "disabled";
 		};
 
+		rtc: rtc@58004000 {
+			compatible = "st,stm32h7-rtc";
+			reg = <0x58004000 0x400>;
+			clocks = <&rcc RTCAPB_CK>, <&rcc RTC_CK>;
+			clock-names = "pclk", "rtc_ck";
+			assigned-clocks = <&rcc RTC_CK>;
+			assigned-clock-parents = <&rcc LSE_CK>;
+			interrupt-parent = <&exti>;
+			interrupts = <17 IRQ_TYPE_EDGE_RISING>;
+			interrupt-names = "alarm";
+			st,syscfg = <&pwrcfg>;
+			status = "disabled";
+		};
+
 		rcc: reset-clock-controller@58024400 {
 			compatible = "st,stm32h743-rcc", "st,stm32-rcc";
 			reg = <0x58024400 0x400>;