drm: Remove some unused stuff from drm_plane

There's a bunch of unused members inside drm_plane, bloating the size of
the structure needlessly. Eliminate them.

v2: Remove all of it from kernel-doc too

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@gmail.com>

drivers/gpu/drm/drm_crtc.c

@@ -1805,7 +1805,7 @@ int drm_mode_getplane(struct drm_device *dev, void *data,
 
 	plane_resp->plane_id = plane->base.id;
 	plane_resp->possible_crtcs = plane->possible_crtcs;
-	plane_resp->gamma_size = plane->gamma_size;
+	plane_resp->gamma_size = 0;
 
 	/*
 	 * This ioctl is called twice, once to determine how much space is

include/drm/drm_crtc.h

@@ -654,11 +654,7 @@ struct drm_plane_funcs {
  * @format_count: number of formats supported
  * @crtc: currently bound CRTC
  * @fb: currently bound fb
- * @gamma_size: size of gamma table
- * @gamma_store: gamma correction table
- * @enabled: enabled flag
  * @funcs: helper functions
- * @helper_private: storage for drver layer
  * @properties: property tracking for this plane
  */
 struct drm_plane {
@@ -674,14 +670,7 @@ struct drm_plane {
 	struct drm_crtc *crtc;
 	struct drm_framebuffer *fb;
 
-	/* CRTC gamma size for reporting to userspace */
-	uint32_t gamma_size;
-	uint16_t *gamma_store;
-
-	bool enabled;
-
 	const struct drm_plane_funcs *funcs;
-	void *helper_private;
 
 	struct drm_object_properties properties;
 };