arm64: dts: freescale: imx8dxl-evk: enable mii_select node

The mii_select node is used to determine the fec1's interface
type. Using "enable-active-high" property to configure the
interface type as "RMII". Deleting the property as "RGMII".
Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8dxl-evk.dts

@@ -90,6 +90,16 @@ reg_usdhc2_vmmc: regulator-3 {
 		enable-active-high;
 		off-on-delay-us = <3480>;
 	};
+
+	mii_select: regulator-4 {
+		compatible = "regulator-fixed";
+		regulator-name = "mii-select";
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		gpio = <&scu_gpio 6 GPIO_ACTIVE_HIGH>;
+		enable-active-high;
+		regulator-always-on;
+	};
 };
 
 &eqos {