ARM: dts: dra7-evm: Correct the vmmc-supply for mmc2

On DRA75x EVM, MMC2 vdd/ios are connected to a common supply fixed at 1.8V
not 3.3V

Fixes: 6cf02dbb ("ARM: dts: dra7-evm: Add mmc2 node for eMMC support")
Signed-off-by: Ravikumar Kattekola <rk@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/dra7-evm.dts

@@ -25,6 +25,14 @@ chosen {
 		stdout-path = &uart1;
 	};
 
+	evm_1v8_sw: fixedregulator-evm_1v8 {
+		compatible = "regulator-fixed";
+		regulator-name = "evm_1v8";
+		vin-supply = <&smps9_reg>;
+		regulator-min-microvolt = <1800000>;
+		regulator-max-microvolt = <1800000>;
+	};
+
 	evm_3v3_sd: fixedregulator-sd {
 		compatible = "regulator-fixed";
 		regulator-name = "evm_3v3_sd";
@@ -449,7 +457,7 @@ &mmc2 {
 	status = "okay";
 	pinctrl-names = "default";
 	pinctrl-0 = <&mmc2_pins_default>;
-	vmmc-supply = <&evm_3v3_sw>;
+	vmmc-supply = <&evm_1v8_sw>;
 	bus-width = <8>;
 };