ARM: dts: rockchip: Fix GMAC description n RK3288 boards

According to rockchip-dwmac.yaml, the mdio node should be 'mdio0' and
'wakeup-source' is not a valid property.

Change it accordingly.

This fixes the following dt-schema warning:

Unevaluated properties are not allowed ('mdio0', 'wakeup-source'\
were unexpected)

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Link: https://patch.msgid.link/20260303193855.828892-3-festevam@gmail.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

Author: fabioestevam

arch/arm/boot/dts/rockchip/rk3288-phycore-som.dtsi

@@ -100,7 +100,7 @@
 	tx_delay = <0x0>;
 	rx_delay = <0x0>;
 
-	mdio0 {
+	mdio {
 		compatible = "snps,dwmac-mdio";
 		#address-cells = <1>;
 		#size-cells = <0>;

arch/arm/boot/dts/rockchip/rk3288-veyron-fievel.dts

@@ -98,9 +98,8 @@
 	snps,reset-gpio = <&gpio4 RK_PB0 0>;
 	snps,reset-active-low;
 	snps,reset-delays-us = <0 10000 30000>;
-	wakeup-source;
 
-	mdio0 {
+	mdio {
 		compatible = "snps,dwmac-mdio";
 		#address-cells = <1>;
 		#size-cells = <0>;