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/drivers/gpu/drm/drm_auth.c b/drivers/gpu/drm/drm_auth.c
index 860cfe1..7ff6973 100644
--- a/drivers/gpu/drm/drm_auth.c
+++ b/drivers/gpu/drm/drm_auth.c
@@ -40,8 +40,8 @@
  * least once successfully became the device master (either through the
  * SET_MASTER IOCTL, or implicitly through opening the primary device node when
  * no one else is the current master that time) there exists one &drm_master.
- * This is noted in the is_master member of &drm_file. All other clients have
- * just a pointer to the &drm_master they are associated with.
+ * This is noted in &drm_file.is_master. All other clients have just a pointer
+ * to the &drm_master they are associated with.
  *
  * In addition only one &drm_master can be the current master for a &drm_device.
  * It can be switched through the DROP_MASTER and SET_MASTER IOCTL, or