drm/rockchip: Add MIPI DSI2 glue driver for RK3588

This adds the glue code for the MIPI DSI2 bridge on Rockchip SoCs and
enables its use on the RK3588.

Right now the DSI2 controller is always paired with a DC-phy based on a
Samsung IP, so the interface values are set statically for now.
This stays true for the upcoming RK3576 as well.

Tested-by: Daniel Semkowicz <dse@thaumatec.com>
Tested-by: Dmitry Yashin <dmt.yashin@gmail.com>
Signed-off-by: Heiko Stuebner <heiko.stuebner@cherry.de>
Reviewed-by: Andy Yan <andy.yan@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20241209231021.2180582-4-heiko@sntech.de