drm: fix typos in plane and CRTC overviews

Fix one missing letter, and one duplicate struct field reference.
Signed-off-by: Simon Ser <contact@emersion.fr>
Cc: Daniel Vetter <daniel@ffwll.ch>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/3gESG7rm6lCex6qBZnl3YXTfefKZODEvJ4DX4RoI1cY@cp4-web-040.plabs.ch

drivers/gpu/drm/drm_crtc.c

@@ -67,7 +67,7 @@
  * &drm_crtc_funcs.page_flip and &drm_crtc_funcs.cursor_set2, and other legacy
  * operations like &drm_crtc_funcs.gamma_set. For atomic drivers all these
  * features are controlled through &drm_property and
- * &drm_mode_config_funcs.atomic_check and &drm_mode_config_funcs.atomic_check.
+ * &drm_mode_config_funcs.atomic_check.
  */
 
 /**

drivers/gpu/drm/drm_plane.c

@@ -40,7 +40,7 @@
  * A plane represents an image source that can be blended with or overlayed on
  * top of a CRTC during the scanout process. Planes take their input data from a
  * &drm_framebuffer object. The plane itself specifies the cropping and scaling
- * of that image, and where it is placed on the visible are of a display
+ * of that image, and where it is placed on the visible area of a display
  * pipeline, represented by &drm_crtc. A plane can also have additional
  * properties that specify how the pixels are positioned and blended, like
  * rotation or Z-position. All these properties are stored in &drm_plane_state.