ARM: dts: imx6qdl-skov-cpu: configure ethernet reference clock parent

On this board the PHY is the ref clock provider. So, configure ethernet
reference clock as input.
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6qdl-skov-cpu.dtsi

@@ -105,6 +105,7 @@ clk50m_phy: phy-clock {
 		compatible = "fixed-clock";
 		#clock-cells = <0>;
 		clock-frequency = <50000000>;
+		clock-output-names = "enet_ref_pad";
 	};
 
 	reg_3v3: regulator-3v3 {
@@ -232,13 +233,16 @@ adc: adc@0 {
 	};
 };
 
+&clks {
+	clocks = <&clk50m_phy>;
+	clock-names = "enet_ref_pad";
+	assigned-clocks = <&clks IMX6QDL_CLK_ENET_REF_SEL>;
+	assigned-clock-parents = <&clk50m_phy>;
+};
+
 &fec {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_enet>;
-	clocks = <&clks IMX6QDL_CLK_ENET>,
-		 <&clks IMX6QDL_CLK_ENET>,
-		 <&clk50m_phy>;
-	clock-names = "ipg", "ahb", "ptp";
 	phy-mode = "rmii";
 	phy-supply = <&reg_3v3>;
 	status = "okay";