ARM: dts: r8a7742-iwg21d-q7: Enable Ethernet AVB

Enable Ethernet AVB on iWave RZ/G1H carrier board.
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Marian-Cristian Rotariu <marian-cristian.rotariu.rb@bp.renesas.com>
Link: https://lore.kernel.org/r/1590420129-7531-4-git-send-email-prabhakar.mahadev-lad.rj@bp.renesas.comSigned-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

arch/arm/boot/dts/r8a7742-iwg21d-q7.dts

@@ -15,6 +15,7 @@ / {
 	aliases {
 		serial2 = &scifa2;
 		serial4 = &scifb2;
+		ethernet0 = &avb;
 	};
 
 	chosen {
@@ -45,7 +46,27 @@ vccq_sdhi2: regulator-vccq-sdhi2 {
 	};
 };
 
+&avb {
+	pinctrl-0 = <&avb_pins>;
+	pinctrl-names = "default";
+
+	phy-handle = <&phy3>;
+	phy-mode = "gmii";
+	renesas,no-ether-link;
+	status = "okay";
+
+	phy3: ethernet-phy@3 {
+		reg = <3>;
+		micrel,led-mode = <1>;
+	};
+};
+
 &pfc {
+	avb_pins: avb {
+		groups = "avb_mdio", "avb_gmii";
+		function = "avb";
+	};
+
 	scifa2_pins: scifa2 {
 		groups = "scifa2_data_c";
 		function = "scifa2";