ARM: dts: rockchip: add input supplies for the act8846 on Radxa Rock

On the Radxa Rock board most supplies come from the static 5v vsys supply, but
the inl1-supply comes from the REG4 of the act8846 itself. Model this dependency
using the added supply-handling to make sure the supplying regulator gets handled
correctly and not accidentially turned off.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm/boot/dts/rk3188-radxarock.dts

@@ -103,6 +103,14 @@ vcc_host: usb-host-regulator {
 		regulator-always-on;
 		regulator-boot-on;
 	};
+
+	vsys: vsys-regulator {
+		compatible = "regulator-fixed";
+		regulator-name = "vsys";
+		regulator-min-microvolt = <5000000>;
+		regulator-max-microvolt = <5000000>;
+		regulator-boot-on;
+	};
 };
 
 &emac {
@@ -148,6 +156,14 @@ act8846: act8846@5a {
 		pinctrl-names = "default";
 		pinctrl-0 = <&act8846_dvs0_ctl>;
 
+		vp1-supply = <&vsys>;
+		vp2-supply = <&vsys>;
+		vp3-supply = <&vsys>;
+		vp4-supply = <&vsys>;
+		inl1-supply = <&vcc_io>;
+		inl2-supply = <&vsys>;
+		inl3-supply = <&vsys>;
+
 		regulators {
 			vcc_ddr: REG1 {
 				regulator-name = "VCC_DDR";