Tommy Chen authored May 29, 2023 and Tommy Chen committed May 30, 2023

add has_gamma flag to mtk_disp_gamma_data, and use it to decide if a
platform supports gamma or not.

add compatible mediatek,mt8195-disp-gamma to indicate gamma not support for now.
mt8365, mt8188, and mt8195 all use mediatek,mt8195-disp-gamma

for each platform, the supporting status for has_dither and has_gamma are as follows
mt8173:has_dither = true,  has_gamma = true;
mt8183:has_dither = false, has_gamma = true;
mt8365, mt8188, and mt8195: not defined driver data, which equals
       has_dither = false, has_gamma = false;

Change-Id: Icb79ff3a5a099bed2ded46c50d6cc031dedef6eb
Signed-off-by: Tommy Chen <tommyyl.chen@mediatek.com>