drm/rockchip: rk3066_hdmi: switch to drm bridge

drm/rockchip: rk3066_hdmi: switch to drm bridge

Convert it to drm bridge driver, it will be convenient for us to
migrate the connector part to the display driver later.

Note: I don't have the hardware to test this driver, so for now
I can only do the compilation test.

Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
Tested-by: Heiko Stuebner <heiko@sntech.de> #rk3066-marsboard
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/20250428102309.1501986-1-andyshrk@163.com