arm64: dts: allwinner: h5: OrangePi PC2: Fix ethernet node

RX and TX delay are provided by ethernet PHY. Reflect that in ethernet
node.

Fixes: 44a94c7e ("arm64: dts: allwinner: H5: Restore EMAC changes")
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20201023184858.3272918-1-jernej.skrabec@siol.net

arch/arm64/boot/dts/allwinner/sun50i-h5-orangepi-pc2.dts

@@ -123,7 +123,7 @@ &emac {
 	pinctrl-0 = <&emac_rgmii_pins>;
 	phy-supply = <&reg_gmac_3v3>;
 	phy-handle = <&ext_rgmii_phy>;
-	phy-mode = "rgmii";
+	phy-mode = "rgmii-id";
 	status = "okay";
 };