arm64: zynqmp: Use mdio node by vp-x-a2785-00-revA and vpk120-revA

All boards have been converted to use mdio node that's why move ethernet
phys under mdio node too.

Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/6c60f5d29b9d9992bd0130fd263c8ed13cb8166c.1697115523.git.michal.simek@amd.com
diff --git a/arch/arm/dts/zynqmp-vp-x-a2785-00-revA.dts b/arch/arm/dts/zynqmp-vp-x-a2785-00-revA.dts
index 2f88aa4..9ab8f5b 100644
--- a/arch/arm/dts/zynqmp-vp-x-a2785-00-revA.dts
+++ b/arch/arm/dts/zynqmp-vp-x-a2785-00-revA.dts
@@ -119,9 +119,13 @@
 	phy-mode = "sgmii"; /* DTG generates this properly 1512 */
 	is-internal-pcspma;
 	/* phys = <&psgtr 0 PHY_TYPE_SGMII 0 0>; */
-	/* phy-reset-gpios = <&gpio 142 GPIO_ACTIVE_LOW>; */
-	phy0: ethernet-phy@0 { /* u131 - M88e1512 */
-		reg = <0>;
+	mdio: mdio {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		/* reset-gpios = <&gpio 142 GPIO_ACTIVE_LOW>; */
+		phy0: ethernet-phy@0 { /* u131 - M88e1512 */
+			reg = <0>;
+		};
 	};
 };