drm/ast: Do not call drm_atomic_add_affected_planes()

There's no need to add planes to the atomic state. Remove the call
to drm_atomic_add_affected_planes() from ast.

On full modesets, the DRM helpers already add a CRTC's planes to the
atomic state; see drm_atomic_helper_check_modeset(). There's no reason
to call drm_atomic_add_affected_planes() unconditionally in the CRTC's
atomic_check() in ast. It's also too late, as the atomic_check() of
the added planes will not be called before the commit.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>
Tested-by: Jocelyn Falempe <jfalempe@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221013112923.769-4-tzimmermann@suse.de

drivers/gpu/drm/ast/ast_mode.c

@@ -1157,7 +1157,7 @@ static int ast_crtc_helper_atomic_check(struct drm_crtc *crtc,
 	int ret;
 
 	if (!crtc_state->enable)
-		goto out;
+		return 0;
 
 	ret = drm_atomic_helper_check_crtc_primary_plane(crtc_state);
 	if (ret)
@@ -1191,8 +1191,7 @@ static int ast_crtc_helper_atomic_check(struct drm_crtc *crtc,
 	if (!succ)
 		return -EINVAL;
 
-out:
-	return drm_atomic_add_affected_planes(state, crtc);
+	return 0;
 }
 
 static void