drm/stm: ltdc: Drop format_mod_supported function

The "drm_plane_funcs.format_mod_supported" can be removed in favor of
the default implementation.
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Reviewed-by: Yannick Fertre <yannick.fertre@foss.st.com>
Tested-by: Yannick Fertre <yannick.fertre@foss.st.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com> # i.Core STM32MP1
Signed-off-by: Philippe Cornu <philippe.cornu@foss.st.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211222090552.25972-7-jose.exposito89@gmail.com

drivers/gpu/drm/stm/ltdc.c

@@ -1353,16 +1353,6 @@ static void ltdc_plane_atomic_print_state(struct drm_printer *p,
 	fpsi->counter = 0;
 }
 
-static bool ltdc_plane_format_mod_supported(struct drm_plane *plane,
-					    u32 format,
-					    u64 modifier)
-{
-	if (modifier == DRM_FORMAT_MOD_LINEAR)
-		return true;
-
-	return false;
-}
-
 static const struct drm_plane_funcs ltdc_plane_funcs = {
 	.update_plane = drm_atomic_helper_update_plane,
 	.disable_plane = drm_atomic_helper_disable_plane,
@@ -1371,7 +1361,6 @@ static const struct drm_plane_funcs ltdc_plane_funcs = {
 	.atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
 	.atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
 	.atomic_print_state = ltdc_plane_atomic_print_state,
-	.format_mod_supported = ltdc_plane_format_mod_supported,
 };
 
 static const struct drm_plane_helper_funcs ltdc_plane_helper_funcs = {