rockchip: usb: host: xhci-rockchip: add support for rk3328

Add the compatible "rockchip,rk3328-xhci" in match table
for rk3328 to probe xhci controller. Use fixed regulator
to control the voltage of vbus and turn off vbus when
usb stop.

Signed-off-by: Meng Dongyang <daniel.meng@rock-chips.com>
Reviewed-by: Simon Glass <sjg@chromium.org>