ARM: dts: Add usb2phy support on exynos5420

Add required device node for usb2phy to let enable USB 2.0
support.

Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
Signed-off-by: Vikas Sajjan <vikas.sajjan@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

arch/arm/boot/dts/exynos5420.dtsi

@@ -815,4 +815,14 @@
 		samsung,pmu-syscon = <&pmu_system_controller>;
 		#phy-cells = <1>;
 	};
+
+	usb2_phy: phy@12130000 {
+		compatible = "samsung,exynos5250-usb2-phy";
+		reg = <0x12130000 0x100>;
+		clocks = <&clock CLK_USBH20>, <&clock CLK_SCLK_USBPHY300>;
+		clock-names = "phy", "ref";
+		#phy-cells = <1>;
+		samsung,sysreg-phandle = <&sysreg_system_controller>;
+		samsung,pmureg-phandle = <&pmu_system_controller>;
+	};
 };