riscv: dts: enable more DA9063 functions for the SiFive HiFive Unmatched

The DA9063 PMIC found on the SiFive HiFive Unmatched also provides an
RTC, a watchdog and the power button input.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

arch/riscv/boot/dts/sifive/hifive-unmatched-a00.dts

@@ -65,6 +65,10 @@ pmic@58 {
 		interrupts = <1 IRQ_TYPE_LEVEL_LOW>;
 		interrupt-controller;
 
+		onkey {
+			compatible = "dlg,da9063-onkey";
+		};
+
 		regulators {
 			vdd_bcore1: bcore1 {
 				regulator-min-microvolt = <900000>;
@@ -200,6 +204,14 @@ vdd_ldo11: ldo11 {
 				regulator-always-on;
 			};
 		};
+
+		rtc {
+			compatible = "dlg,da9063-rtc";
+		};
+
+		wdt {
+			compatible = "dlg,da9063-watchdog";
+		};
 	};
 };