arm64: allwinner: pine64: Enable dwmac-sun8i

The dwmac-sun8i hardware is present on the pine64
It uses an external PHY via RMII.
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

arch/arm64/boot/dts/allwinner/sun50i-a64-pine64.dts

@@ -78,6 +78,15 @@ &ehci1 {
 	status = "okay";
 };
 
+&emac {
+	pinctrl-names = "default";
+	pinctrl-0 = <&rmii_pins>;
+	phy-mode = "rmii";
+	phy-handle = <&ext_rmii_phy1>;
+	status = "okay";
+
+};
+
 &i2c1 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&i2c1_pins>;
@@ -88,6 +97,13 @@ &i2c1_pins {
 	bias-pull-up;
 };
 
+&mdio {
+	ext_rmii_phy1: ethernet-phy@1 {
+		compatible = "ethernet-phy-ieee802.3-c22";
+		reg = <1>;
+	};
+};
+
 &mmc0 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&mmc0_pins>;