ARM: dts: sun4i/sun7i: add RTC node

Add the RTC node to DTS for Allwinner A10 and Allwinner A20.

Signed-off-by: Carlo Caione <carlo.caione@gmail.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
diff --git a/arch/arm/boot/dts/sun7i-a20.dtsi b/arch/arm/boot/dts/sun7i-a20.dtsi
index e46cfed..830fcd5 100644
--- a/arch/arm/boot/dts/sun7i-a20.dtsi
+++ b/arch/arm/boot/dts/sun7i-a20.dtsi
@@ -265,6 +265,12 @@
 			reg = <0x01c20c90 0x10>;
 		};
 
+		rtc: rtc@01c20d00 {
+			compatible = "allwinner,sun7i-a20-rtc";
+			reg = <0x01c20d00 0x20>;
+			interrupts = <0 24 1>;
+		};
+
 		sid: eeprom@01c23800 {
 			compatible = "allwinner,sun7i-a20-sid";
 			reg = <0x01c23800 0x200>;