arm64: dts: allwinner: h6: add system controller device tree node

As we have already binding for the H6 system controller, add its node
to the device tree.
Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
[fixed compatible string]
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>

arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi

@@ -92,6 +92,29 @@ soc {
 		#size-cells = <1>;
 		ranges;
 
+		syscon: syscon@3000000 {
+			compatible = "allwinner,sun50i-h6-system-control",
+				     "allwinner,sun50i-a64-system-control";
+			reg = <0x03000000 0x1000>;
+			#address-cells = <1>;
+			#size-cells = <1>;
+			ranges;
+
+			sram_c: sram@28000 {
+				compatible = "mmio-sram";
+				reg = <0x00028000 0x1e000>;
+				#address-cells = <1>;
+				#size-cells = <1>;
+				ranges = <0 0x00028000 0x1e000>;
+
+				de2_sram: sram-section@0 {
+					compatible = "allwinner,sun50i-h6-sram-c",
+						     "allwinner,sun50i-a64-sram-c";
+					reg = <0x0000 0x1e000>;
+				};
+			};
+		};
+
 		ccu: clock@3001000 {
 			compatible = "allwinner,sun50i-h6-ccu";
 			reg = <0x03001000 0x1000>;