arm64: dts: allwinner: h5: libretech-all-h5-cc: Enable RGMII RX/TX delay on PHY

The Ethernet PHY on the Libre Computer ALL-H5-CC has the RX and TX
delays enabled on the PHY, using pull-ups on the RXDLY and TXDLY pins.

Fix the phy-mode description to correct reflect this so that the
implementation doesn't reconfigure the delays incorrectly. This
happened with commit bbc4d71d ("net: phy: realtek: fix rtl8211e
rx/tx delay config").

Fixes: 60d0426d ("arm64: dts: allwinner: h5: Add Libre Computer ALL-H5-CC H5 board")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Jernej Skrabec <jernej.skrabec@siol.net>
Link: https://lore.kernel.org/r/20201024162515.30032-9-wens@kernel.org

arch/arm64/boot/dts/allwinner/sun50i-h5-libretech-all-h5-cc.dts

@@ -36,7 +36,7 @@ &emac {
 	pinctrl-0 = <&emac_rgmii_pins>;
 	phy-supply = <&reg_gmac_3v3>;
 	phy-handle = <&ext_rgmii_phy>;
-	phy-mode = "rgmii";
+	phy-mode = "rgmii-id";
 	/delete-property/ allwinner,leds-active-low;
 	status = "okay";
 };