phy: add Rockchip Innosilicon hdmi phy

Add a driver for the Innosilicon hdmi phy used on rk3228/rk3229
and rk3328 socs from Rockchip.

Signed-off-by: Zheng Yang <zhengyang@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>