drm/panel: himax-hx8394: Add Support for Powkiddy X55 panel

Add support for the Powkiddy X55 panel as used on the Powkiddy X55
handheld gaming console. This panel uses a Himax HX8394 display
controller and requires a vendor provided init sequence. The display
resolution is 720x1280 and is 67mm by 121mm as measured with calipers.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20231204185719.569021-7-macroalpha82@gmail.com


Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231204185719.569021-7-macroalpha82@gmail.com