drm: Fix some typos

Signed-off-by: NJohn Hunter <zhjwpku@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/drm_atomic.c

@@ -780,7 +780,7 @@ drm_atomic_set_crtc_for_plane(struct drm_plane_state *plane_state,
 EXPORT_SYMBOL(drm_atomic_set_crtc_for_plane);
 
 /**
- * drm_atomic_set_fb_for_plane - set crtc for plane
+ * drm_atomic_set_fb_for_plane - set framebuffer for plane
  * @plane_state: atomic state object for the plane
  * @fb: fb to use for the plane
  *