drm/fourcc: Add drm_format_info.is_color_indexed flag

Add a flag to struct drm_format_info to indicate if a format is
color-indexed, similar to the existing .is_yuv flag.

This way generic code and drivers can just check this flag, instead of
checking against a list of fourcc formats.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/90cd390b2b4d481661f966de7b504f1702d80dfd.1657294931.git.geert@linux-m68k.org

drivers/gpu/drm/drm_fourcc.c

@@ -132,7 +132,7 @@ EXPORT_SYMBOL(drm_driver_legacy_fb_format);
 const struct drm_format_info *__drm_format_info(u32 format)
 {
 	static const struct drm_format_info formats[] = {
-		{ .format = DRM_FORMAT_C8,		.depth = 8,  .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_C8,		.depth = 8,  .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1, .is_color_indexed = true },
 		{ .format = DRM_FORMAT_R8,		.depth = 8,  .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1 },
 		{ .format = DRM_FORMAT_R10,		.depth = 10, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
 		{ .format = DRM_FORMAT_R12,		.depth = 12, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },

include/drm/drm_fourcc.h

@@ -138,6 +138,9 @@ struct drm_format_info {
 
 	/** @is_yuv: Is it a YUV format? */
 	bool is_yuv;
+
+	/** @is_color_indexed: Is it a color-indexed format? */
+	bool is_color_indexed;
 };
 
 /**