phy: rockchip: usbdp: Simplify init ops

phy: rockchip: usbdp: Simplify init ops

With working shared reference counting for Generic PHY ops there is no
need for the Rockchip USBDP PHY driver to keep its own status (reference
counting) handling.

Simplify the init ops now that shared reference counting is working.
This also removes the unused mode_change handling as part of the
simplication.

No runtime change is expected with this simplication.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>