drm/bochs: encoder cleanup

Most unused callbacks can be NULL pointers these days.
Drop a bunch of empty encoder callbacks.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20190111053752.4004-2-kraxel@redhat.com

drivers/gpu/drm/bochs/bochs_kms.c

@@ -170,31 +170,6 @@ static void bochs_crtc_init(struct drm_device *dev)
 	drm_crtc_helper_add(crtc, &bochs_helper_funcs);
 }
 
-static void bochs_encoder_mode_set(struct drm_encoder *encoder,
-				   struct drm_display_mode *mode,
-				   struct drm_display_mode *adjusted_mode)
-{
-}
-
-static void bochs_encoder_dpms(struct drm_encoder *encoder, int state)
-{
-}
-
-static void bochs_encoder_prepare(struct drm_encoder *encoder)
-{
-}
-
-static void bochs_encoder_commit(struct drm_encoder *encoder)
-{
-}
-
-static const struct drm_encoder_helper_funcs bochs_encoder_helper_funcs = {
-	.dpms = bochs_encoder_dpms,
-	.mode_set = bochs_encoder_mode_set,
-	.prepare = bochs_encoder_prepare,
-	.commit = bochs_encoder_commit,
-};
-
 static const struct drm_encoder_funcs bochs_encoder_encoder_funcs = {
 	.destroy = drm_encoder_cleanup,
 };
@@ -207,7 +182,6 @@ static void bochs_encoder_init(struct drm_device *dev)
 	encoder->possible_crtcs = 0x1;
 	drm_encoder_init(dev, encoder, &bochs_encoder_encoder_funcs,
 			 DRM_MODE_ENCODER_DAC, NULL);
-	drm_encoder_helper_add(encoder, &bochs_encoder_helper_funcs);
 }