drm/mediatek: remove unused external function

layer_on and layer_off both are unused external function,
remove them from mtk_ddp_comp_funcs structure.
Signed-off-by: Bibby Hsieh <bibby.hsieh@mediatek.com>
Signed-off-by: CK Hu <ck.hu@mediatek.com>

drivers/gpu/drm/mediatek/mtk_disp_ovl.c

@@ -313,8 +313,6 @@ static const struct mtk_ddp_comp_funcs mtk_disp_ovl_funcs = {
 	.disable_vblank = mtk_ovl_disable_vblank,
 	.supported_rotations = mtk_ovl_supported_rotations,
 	.layer_nr = mtk_ovl_layer_nr,
-	.layer_on = mtk_ovl_layer_on,
-	.layer_off = mtk_ovl_layer_off,
 	.layer_check = mtk_ovl_layer_check,
 	.layer_config = mtk_ovl_layer_config,
 	.bgclr_in_on = mtk_ovl_bgclr_in_on,

drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h

@@ -79,8 +79,6 @@ struct mtk_ddp_comp_funcs {
 	void (*disable_vblank)(struct mtk_ddp_comp *comp);
 	unsigned int (*supported_rotations)(struct mtk_ddp_comp *comp);
 	unsigned int (*layer_nr)(struct mtk_ddp_comp *comp);
-	void (*layer_on)(struct mtk_ddp_comp *comp, unsigned int idx);
-	void (*layer_off)(struct mtk_ddp_comp *comp, unsigned int idx);
 	int (*layer_check)(struct mtk_ddp_comp *comp,
 			   unsigned int idx,
 			   struct mtk_plane_state *state);
@@ -151,20 +149,6 @@ static inline unsigned int mtk_ddp_comp_layer_nr(struct mtk_ddp_comp *comp)
 	return 0;
 }
 
-static inline void mtk_ddp_comp_layer_on(struct mtk_ddp_comp *comp,
-					 unsigned int idx)
-{
-	if (comp->funcs && comp->funcs->layer_on)
-		comp->funcs->layer_on(comp, idx);
-}
-
-static inline void mtk_ddp_comp_layer_off(struct mtk_ddp_comp *comp,
-					  unsigned int idx)
-{
-	if (comp->funcs && comp->funcs->layer_off)
-		comp->funcs->layer_off(comp, idx);
-}
-
 static inline int mtk_ddp_comp_layer_check(struct mtk_ddp_comp *comp,
 					   unsigned int idx,
 					   struct mtk_plane_state *state)