arm64: dts: Add X-Gene v2 reboot driver dts node

This patch add dts nodes for X-Gene v2 (APM X-Gene Shadowcat SoC)
platforms to use generic SYSCON regmap reset driver for its reset
operation.
Signed-off-by: Duc Dang <dhdang@apm.com>

arch/arm64/boot/dts/apm/apm-shadowcat.dtsi

@@ -172,6 +172,18 @@ xge1clk: xge1clk@1f62c000 {
 			};
 		};
 
+		scu: system-clk-controller@17000000 {
+			compatible = "apm,xgene-scu","syscon";
+			reg = <0x0 0x17000000 0x0 0x400>;
+		};
+
+		reboot: reboot@17000014 {
+			compatible = "syscon-reboot";
+			regmap = <&scu>;
+			offset = <0x14>;
+			mask = <0x1>;
+		};
+
 		serial0: serial@10600000 {
 			device_type = "serial";
 			compatible = "ns16550";