dt-bindings: phy: imx8mq-usb: add power-domains property

Add optional power-domains property for usb phy.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Acked-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20221014095550.2125018-1-peng.fan@oss.nxp.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>