arm: dts: phy3250: add SD fixed regulator

The change adds fixed voltage regulator for SD controller, ARM MMCI
controller driver uses it to control card power management.
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>

arch/arm/boot/dts/phy3250.dts

@@ -45,6 +45,15 @@ lcd_reg: regulator@1 {
 			enable-active-high;
 			regulator-boot-on;
 		};
+
+		sd_reg: regulator@2 {
+			compatible = "regulator-fixed";
+			regulator-name = "sd_reg";
+			regulator-min-microvolt = <1800000>;
+			regulator-max-microvolt = <1800000>;
+			gpio = <&gpio 5 5 0>;
+			enable-active-high;
+		};
 	};
 
 	ahb {
@@ -162,6 +171,7 @@ sd@20098000 {
 				cd-gpios = <&gpio 3 1 0>;
 				cd-inverted;
 				bus-width = <4>;
+				vmmc-supply = <&sd_reg>;
 				status = "okay";
 			};
 		};