ARM: dts: imx6qdl-icore: Add fec phy-handle

LAN8720 needs a reset of every clock enable. The reset needs
to be done at device level, due the flag PHY_RST_AFTER_CLK_EN.

So, add phy-handle by creating mdio child node inside fec.
This will eventually move the phy-reset-gpio which is defined
in fec node.
Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6qdl-icore.dtsi

@@ -150,10 +150,23 @@ &clks {
 &fec {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_enet>;
-	phy-reset-gpios = <&gpio7 12 GPIO_ACTIVE_LOW>;
 	clocks = <&clks IMX6QDL_CLK_ENET>, <&clks IMX6QDL_CLK_ENET>, <&rmii_clk>;
 	phy-mode = "rmii";
+	phy-handle = <&eth_phy>;
 	status = "okay";
+
+	mdio {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		eth_phy: ethernet-phy@0 {
+			compatible = "ethernet-phy-ieee802.3-c22";
+			reg = <0>;
+			reset-gpios = <&gpio7 12 GPIO_ACTIVE_LOW>;
+			reset-assert-us = <4000>;
+			reset-deassert-us = <4000>;
+		};
+	};
 };
 
 &gpmi {