drm/atomic-helpers: Fix documentation typos and wrong copy&paste

The kerneldoc blocks for the drm_atomic_helper_*_set_property()
functions seem to have been copied from the plane disable handler
without being properly updated. Fix them.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/drm_atomic_helper.c

@@ -1678,12 +1678,13 @@ backoff:
 EXPORT_SYMBOL(drm_atomic_helper_set_config);
 
 /**
- * drm_atomic_helper_crtc_set_property - helper for crtc prorties
+ * drm_atomic_helper_crtc_set_property - helper for crtc properties
  * @crtc: DRM crtc
  * @property: DRM property
  * @val: value of property
  *
- * Provides a default plane disablle handler using the atomic driver interface.
+ * Provides a default crtc set_property handler using the atomic driver
+ * interface.
  *
  * RETURNS:
  * Zero on success, error code on failure
@@ -1737,12 +1738,13 @@ backoff:
 EXPORT_SYMBOL(drm_atomic_helper_crtc_set_property);
 
 /**
- * drm_atomic_helper_plane_set_property - helper for plane prorties
+ * drm_atomic_helper_plane_set_property - helper for plane properties
  * @plane: DRM plane
  * @property: DRM property
  * @val: value of property
  *
- * Provides a default plane disable handler using the atomic driver interface.
+ * Provides a default plane set_property handler using the atomic driver
+ * interface.
  *
  * RETURNS:
  * Zero on success, error code on failure
@@ -1796,12 +1798,13 @@ backoff:
 EXPORT_SYMBOL(drm_atomic_helper_plane_set_property);
 
 /**
- * drm_atomic_helper_connector_set_property - helper for connector prorties
+ * drm_atomic_helper_connector_set_property - helper for connector properties
  * @connector: DRM connector
  * @property: DRM property
  * @val: value of property
  *
- * Provides a default plane disablle handler using the atomic driver interface.
+ * Provides a default connector set_property handler using the atomic driver
+ * interface.
  *
  * RETURNS:
  * Zero on success, error code on failure