ARM: dts: Add cluster regulator supply properties for exynos542x/5800

Add cluster regulator supply properties as a preparation to
adding generic cpufreq-dt driver support for Exynos542x and
Exynos5800 based boards.

Cc: Doug Anderson <dianders@chromium.org>
Cc: Javier Martinez Canillas <javier@osg.samsung.com>
Cc: Andreas Faerber <afaerber@suse.de>
Cc: Thomas Abraham <thomas.ab@samsung.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
diff --git a/arch/arm/boot/dts/exynos5420-smdk5420.dts b/arch/arm/boot/dts/exynos5420-smdk5420.dts
index 1935a0b..0785fed 100644
--- a/arch/arm/boot/dts/exynos5420-smdk5420.dts
+++ b/arch/arm/boot/dts/exynos5420-smdk5420.dts
@@ -90,6 +90,14 @@
 
 };
 
+&cpu0 {
+	cpu-supply = <&buck2_reg>;
+};
+
+&cpu4 {
+	cpu-supply = <&buck6_reg>;
+};
+
 &dp {
 	pinctrl-names = "default";
 	pinctrl-0 = <&dp_hpd>;