arm64: dts: Add reboot node for exynos7

This patch add syscon-reboot node to reboot exynos7 based SoCs.
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

arch/arm64/boot/dts/exynos/exynos7.dtsi

@@ -454,6 +454,13 @@ pmu_system_controller: system-controller@105c0000 {
 			reg = <0x105c0000 0x5000>;
 		};
 
+		reboot: syscon-reboot {
+			compatible = "syscon-reboot";
+			regmap = <&pmu_system_controller>;
+			offset = <0x0400>;
+			mask = <0x1>;
+		};
+
 		rtc: rtc@10590000 {
 			compatible = "samsung,s3c6410-rtc";
 			reg = <0x10590000 0x100>;