drm/format-helper: Add XRGB8888-to-RGB332 to drm_fb_blit()

List the conversion from XRGB8888-to-RGB332 in drm_fb_blit(), so that
drivers based on sysfb-helpers can use it.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250714151513.309475-7-tzimmermann@suse.de

Author: tdz

drivers/gpu/drm/drm_format_helper.c

@@ -1243,6 +1243,9 @@ int drm_fb_blit(struct iosys_map *dst, const unsigned int *dst_pitch, uint32_t d
 		} else if (dst_format == DRM_FORMAT_BGRX8888) {
 			drm_fb_swab(dst, dst_pitch, src, fb, clip, false, state);
 			return 0;
+		} else if (dst_format == DRM_FORMAT_RGB332) {
+			drm_fb_xrgb8888_to_rgb332(dst, dst_pitch, src, fb, clip, state);
+			return 0;
 		}
 	}