drm/sun4i: tcon: Don't rely on encoders to set the TCON mode

Just like we did for the TCON enable and disable, for historical reasons we
used to rely on the encoders calling the TCON mode_set function, while the
CRTC has a callback for that.

Let's implement it in order to reduce the boilerplate code.

Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Link: https://patchwork.freedesktop.org/patch/msgid/faa3a4d511039af1d116270dfef3a8b60ca3591e.1508231063.git-series.maxime.ripard@free-electrons.com

drivers/gpu/drm/sun4i/sun4i_tcon.h

@@ -191,15 +191,10 @@ struct drm_bridge *sun4i_tcon_find_bridge(struct device_node *node);
 struct drm_panel *sun4i_tcon_find_panel(struct device_node *node);
 
 void sun4i_tcon_enable_vblank(struct sun4i_tcon *tcon, bool enable);
+void sun4i_tcon_mode_set(struct sun4i_tcon *tcon,
+			 const struct drm_encoder *encoder,
+			 const struct drm_display_mode *mode);
 void sun4i_tcon_set_status(struct sun4i_tcon *crtc,
 			   const struct drm_encoder *encoder, bool enable);
 
-/* Mode Related Controls */
-void sun4i_tcon_set_mux(struct sun4i_tcon *tcon, int channel,
-			struct drm_encoder *encoder);
-void sun4i_tcon0_mode_set(struct sun4i_tcon *tcon,
-			  struct drm_display_mode *mode);
-void sun4i_tcon1_mode_set(struct sun4i_tcon *tcon,
-			  struct drm_display_mode *mode);
-
 #endif /* __SUN4I_TCON_H__ */