ARM: dts: Add fixed voltage regulator to simple bus for origen

This has been done for Arndale board vide commit aa3edb65
("ARM: dts: Put Arndale fixed voltage regulators on a simple-bus").
Replicate here for consistency and correctness.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
diff --git a/arch/arm/boot/dts/exynos4412-origen.dts b/arch/arm/boot/dts/exynos4412-origen.dts
index 8768b03..d65984c 100644
--- a/arch/arm/boot/dts/exynos4412-origen.dts
+++ b/arch/arm/boot/dts/exynos4412-origen.dts
@@ -32,13 +32,20 @@
 		reg = <0x0203F000 0x1000>;
 	};
 
-	mmc_reg: voltage-regulator {
-		compatible = "regulator-fixed";
-		regulator-name = "VMEM_VDD_2.8V";
-		regulator-min-microvolt = <2800000>;
-		regulator-max-microvolt = <2800000>;
-		gpio = <&gpx1 1 0>;
-		enable-active-high;
+	regulators {
+		compatible = "simple-bus";
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		mmc_reg: regulator@0 {
+			compatible = "regulator-fixed";
+			reg = <0>;
+			regulator-name = "VMEM_VDD_2.8V";
+			regulator-min-microvolt = <2800000>;
+			regulator-max-microvolt = <2800000>;
+			gpio = <&gpx1 1 0>;
+			enable-active-high;
+		};
 	};
 
 	pinctrl@11000000 {