ARM: dts: ast2600-evb: Add pinmux properties for enabled MACs

All 2600-evb MACs use RGMII/MDIO.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Joel Stanley <joel@jms.id.au>

arch/arm/boot/dts/aspeed-ast2600-evb.dts

@@ -55,6 +55,9 @@ &mac1 {
 
 	phy-mode = "rgmii";
 	phy-handle = <&ethphy1>;
+
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_rgmii2_default>;
 };
 
 &mac2 {
@@ -62,6 +65,9 @@ &mac2 {
 
 	phy-mode = "rgmii";
 	phy-handle = <&ethphy2>;
+
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_rgmii3_default>;
 };
 
 &mac3 {
@@ -69,6 +75,9 @@ &mac3 {
 
 	phy-mode = "rgmii";
 	phy-handle = <&ethphy3>;
+
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_rgmii4_default>;
 };
 
 &emmc_controller {