drm/mediatek: mtk_dsi: Use simple encoder

The mtk_dsi driver uses an empty implementation for its encoder. Replace
the code with the generic simple encoder.
Signed-off-by: NEnric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NChun-Kuang Hu <chunkuang.hu@kernel.org>

drivers/gpu/drm/mediatek/mtk_dsi.c

@@ -786,15 +786,6 @@ static void mtk_output_dsi_disable(struct mtk_dsi *dsi)
 	dsi->enabled = false;
 }
 
-static void mtk_dsi_encoder_destroy(struct drm_encoder *encoder)
-{
-	drm_encoder_cleanup(encoder);
-}
-
-static const struct drm_encoder_funcs mtk_dsi_encoder_funcs = {
-	.destroy = mtk_dsi_encoder_destroy,
-};
-
 static int mtk_dsi_create_conn_enc(struct drm_device *drm, struct mtk_dsi *dsi);
 static void mtk_dsi_destroy_conn_enc(struct mtk_dsi *dsi);
 
@@ -1124,8 +1115,8 @@ static int mtk_dsi_encoder_init(struct drm_device *drm, struct mtk_dsi *dsi)
 {
 	int ret;
 
-	ret = drm_encoder_init(drm, &dsi->encoder, &mtk_dsi_encoder_funcs,
-			       DRM_MODE_ENCODER_DSI, NULL);
+	ret = drm_simple_encoder_init(drm, &dsi->encoder,
+				      DRM_MODE_ENCODER_DSI);
 	if (ret) {
 		DRM_ERROR("Failed to encoder init to drm\n");
 		return ret;