drm: Docbook fixes

Bunch of small leftovers spotted by looking at the make htmldocs output.

I've left out dp mst, there's too much amiss there.

v2: Also add the missing parameter docbook in the dp mst code - Dave
Airlie correctly pointed out that we don't actually want kerneldoc for
the missing structure members in header files.

Cc: Dave Airlie <airlied@gmail.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/drm_modeset_lock.c b/drivers/gpu/drm/drm_modeset_lock.c
index 5280b64..8749fc0 100644
--- a/drivers/gpu/drm/drm_modeset_lock.c
+++ b/drivers/gpu/drm/drm_modeset_lock.c
@@ -199,7 +199,7 @@
 
 /**
  * drm_modeset_legacy_acquire_ctx - find acquire ctx for legacy ioctls
- * crtc: drm crtc
+ * @crtc: drm crtc
  *
  * Legacy ioctl operations like cursor updates or page flips only have per-crtc
  * locking, and store the acquire ctx in the corresponding crtc. All other