phy: sun4i-usb: Make sure to disable PHY0 passby for peripheral mode

On platforms where the MUSB and HCI controllers share PHY0, PHY passby
is required when using the HCI controller with the PHY, but it must be
disabled when the MUSB controller is used instead.

Without this, PHY0 passby is always enabled, which results in broken
peripheral mode on such platforms (e.g. H3/H5).

Fixes: ba4bdc9e ("PHY: sunxi: Add driver for sunxi usb phy")

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>