ARM: dts: exynos: Fix DTC unit name warnings in Exynos4

Fix following DTC warnings in all Exynos4 boards:

Warning (unit_address_vs_reg): Node /soc/video-phy@10020710 has a unit name, but no reg property
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>

arch/arm/boot/dts/exynos4.dtsi

@@ -82,7 +82,7 @@ sromc@12570000 {
 		reg = <0x12570000 0x14>;
 	};
 
-	mipi_phy: video-phy@10020710 {
+	mipi_phy: video-phy {
 		compatible = "samsung,s5pv210-mipi-video-phy";
 		#phy-cells = <1>;
 		syscon = <&pmu_system_controller>;