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

The reg_module_eth1phy regulator is marked with 'regulator-always-on',
so it is safe to remove it from the eqos node.

Remove it to fix the following schema warning:

imx8mp-verdin-nonwifi-dahlia.dtb: 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>
Tested-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>