[A62][DTS][ETH] fix Gigabit ethernet packet loss

from Documentation/devicetree/bindings/net/ethernet-controller.yaml
the correct way to enable phy skew adjustment is to set
 phy-mode             = "rgmii-id";

arch/arm/boot/dts/seco/seco-imx6qdl-a62.dtsi

@@ -545,7 +545,7 @@ B5 01
 &fec {
 	pinctrl-names        = "default";
 	pinctrl-0            = <&pinctrl_enet>;
-	phy-mode             = "rgmii";
+	phy-mode             = "rgmii-id";
 	phy-supply           = <&reg_phy_pwr>;
 	phy-reset-gpios      = <&gpio3 23 GPIO_ACTIVE_LOW>;
 	phy-reset-duration   = <10>;