phy: rockchip-inno-usb2: Add USB2 PHY for RK3328

USB2.0 Host and OTG controllers in RK3328 are using USB2PHY.

Add support for it.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Reviewed-by: Xavier Drudis Ferran <xdrudis@tinet.cat>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>