ARM: dts: silk: Add DA9063 RTC and OnKey node

Add DA9063 RTC and OnKey subnode to DA9063 PMIC node on Silk.
Signed-off-by: NMarek Vasut <marek.vasut+renesas@gmail.com>
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/r8a7794-silk.dts

@@ -416,6 +416,14 @@
 		interrupts = <31 IRQ_TYPE_LEVEL_LOW>;
 		interrupt-controller;
 
+		onkey {
+			compatible = "dlg,da9063-onkey";
+		};
+
+		rtc {
+			compatible = "dlg,da9063-rtc";
+		};
+
 		wdt {
 			compatible = "dlg,da9063-watchdog";
 		};