arm64: dts: mediatek: rename scpsys nodes to power-controller

The nodes with name scpsys actually implement a power-controller.
Rename the nodes to match the bindings description.
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>

arch/arm64/boot/dts/mediatek/mt2712e.dtsi

@@ -278,7 +278,7 @@ pio: pinctrl@10005000 {
 		interrupts = <GIC_SPI 153 IRQ_TYPE_LEVEL_HIGH>;
 	};
 
-	scpsys: scpsys@10006000 {
+	scpsys: power-controller@10006000 {
 		compatible = "mediatek,mt2712-scpsys", "syscon";
 		#power-domain-cells = <1>;
 		reg = <0 0x10006000 0 0x1000>;

arch/arm64/boot/dts/mediatek/mt6797.dtsi

@@ -157,7 +157,7 @@ pins1 {
 		};
 	};
 
-	scpsys: scpsys@10006000 {
+	scpsys: power-controller@10006000 {
 		compatible = "mediatek,mt6797-scpsys";
 		#power-domain-cells = <1>;
 		reg = <0 0x10006000 0 0x1000>;

arch/arm64/boot/dts/mediatek/mt7622.dtsi

@@ -230,7 +230,7 @@ pericfg: pericfg@10002000 {
 		#reset-cells = <1>;
 	};
 
-	scpsys: scpsys@10006000 {
+	scpsys: power-controller@10006000 {
 		compatible = "mediatek,mt7622-scpsys",
 			     "syscon";
 		#power-domain-cells = <1>;

arch/arm64/boot/dts/mediatek/mt8173.dtsi

@@ -437,7 +437,7 @@ pins1 {
 			};
 		};
 
-		scpsys: scpsys@10006000 {
+		scpsys: power-controller@10006000 {
 			compatible = "mediatek,mt8173-scpsys";
 			#power-domain-cells = <1>;
 			reg = <0 0x10006000 0 0x1000>;