ARM: dts: uniphier: add AVE ethernet node

Add nodes of the AVE ethernet controller for Pro4, PXs2, LD6b SoCs
and the boards.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

arch/arm/boot/dts/uniphier-pro4-ref.dts

@@ -75,6 +75,17 @@
 	status = "okay";
 };
 
+&eth {
+	status = "okay";
+	phy-handle = <&ethphy>;
+};
+
+&mdio {
+	ethphy: ethphy@0 {
+		reg = <0>;
+	};
+};
+
 &nand {
 	status = "okay";
 };