arm64: dts: marvell: Convert 7k/8k usb-phy properties to phy-supply

Update Aramda 7k/8k DTs to use the phy-supply property of the (recent)
generic PHY framework instead of the (legacy) usb-phy preperty. Both
enable the supply when the PHY is enabled.

The COMPHY nodes only provide SERDES lanes configuration. The power
supply that is represented by the phy-supply property is just a
regulator wired to the USB connector, hence the creation of connector
nodes as child of the COMPHY nodes and the supply attached to it.

Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>