arm64: dts: imx8mp-debix-som-a-bmb-08: Remove 'phy-supply' from eqos

Per nxp,dwmac-imx.yaml, it is not valid to pass 'phy-supply'.

Remove it to fix the following dt-schema warning:

ethernet@30bf0000: Unevaluated properties are not allowed ('phy-supply' was unexpected)
	from schema $id: http://devicetree.org/schemas/net/nxp,dwmac-imx.yaml#Signed-off-by: Fabio Estevam <festevam@denx.de>
Reviewed-by: Umang Jain <umang.jain@ideasonboard.com>
Tested-by: Umang Jain <umang.jain@ideasonboard.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mp-debix-som-a-bmb-08.dts

@@ -144,7 +144,6 @@ &eqos {
 	pinctrl-0 = <&pinctrl_eqos>;
 	nvmem-cells = <&ethmac1>;
 	nvmem-cell-names = "mac-address";
-	phy-supply = <&reg_baseboard_vdd3v3>;
 	phy-handle = <&ethphy0>;
 	phy-mode = "rgmii-id";
 	status = "okay";