phy: phy-rockchip-inno-usb2: support #address_cells = 2

New Rockchip devices have the usb phy nodes as standalone devices.
These nodes have register nodes with #address_cells = 2, but only use 32
bit addresses.

Adjust the driver to check if the returned address is "0", and adjust
the index in that case.

Signed-off-by: Peter Geis <pgwipeout@gmail.com>
Tested-by: Michael Riesch <michael.riesch@wolfvision.net>
Link: https://lore.kernel.org/r/20211215210252.120923-4-pgwipeout@gmail.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>