drm: panel: add support for Samsung AMS561RA01 panel with S6E8AA5X01 controller

drm: panel: add support for Samsung AMS561RA01 panel with S6E8AA5X01 controller

Samsung AMS561RA01 is an AMOLED panel, using the Samsung S6E8AA5X01 MIPI
DSI controller. Implement a basic panel driver for such panels.

The driver also initializes a backlight device, which works by changing
the panel's gamma values and aid brightness levels appropriately, with
the help of look-up tables acquired from downstream kernel sources.

Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20250721-panel-samsung-s6e8aa5x01-v5-2-1a315aba530b@disroot.org