drm/core: Use recommened kerneldoc for struct member refs

I just learned that &struct_name.member_name works and looks pretty
even. It doesn't (yet) link to the member directly though, which would
be really good for big structures or vfunc tables (where the
per-member kerneldoc tends to be long).

Also some minor drive-by polish where it makes sense, I read a lot
of docs ...

v2: Review from Gustavo.

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170125062657.19270-6-daniel.vetter@ffwll.ch
diff --git a/include/drm/drm_auth.h b/include/drm/drm_auth.h
index eecbc2f..1eb4a52 100644
--- a/include/drm/drm_auth.h
+++ b/include/drm/drm_auth.h
@@ -43,18 +43,18 @@ struct drm_master {
 	struct kref refcount;
 	struct drm_device *dev;
 	/**
-	 * @unique: Unique identifier: e.g. busid. Protected by struct
-	 * &drm_device master_mutex.
+	 * @unique: Unique identifier: e.g. busid. Protected by
+	 * &drm_device.master_mutex.
 	 */
 	char *unique;
 	/**
-	 * @unique_len: Length of unique field. Protected by &struct drm_device
-	 * master_mutex.
+	 * @unique_len: Length of unique field. Protected by
+	 * &drm_device.master_mutex.
 	 */
 	int unique_len;
 	/**
-	 * @magic_map: Map of used authentication tokens. Protected by struct
-	 * &drm_device master_mutex.
+	 * @magic_map: Map of used authentication tokens. Protected by
+	 * &drm_device.master_mutex.
 	 */
 	struct idr magic_map;
 	struct drm_lock_data lock;