ARM: dts: stm32: enable RTC on stm32429i-eval

This patch enables RTC on stm32429i-eval with default LSE clock source.

Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
diff --git a/arch/arm/boot/dts/stm32429i-eval.dts b/arch/arm/boot/dts/stm32429i-eval.dts
index 2181220..eedb27d 100644
--- a/arch/arm/boot/dts/stm32429i-eval.dts
+++ b/arch/arm/boot/dts/stm32429i-eval.dts
@@ -157,6 +157,10 @@
 	};
 };
 
+&rtc {
+	status = "okay";
+};
+
 &usart1 {
 	pinctrl-0 = <&usart1_pins_a>;
 	pinctrl-names = "default";