drm/doc: Fix more kerneldoc/sphinx warnings

These are the leftovers I could only track down using keep_warnings =
True. For some of them we might want to update our style guide on how
to reference structures and constants, not sure ...

Cc: Markus Heiser <markus.heiser@darmarit.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471034937-651-1-git-send-email-daniel.vetter@ffwll.ch
diff --git a/drivers/gpu/drm/i915/intel_audio.c b/drivers/gpu/drm/i915/intel_audio.c
index d32f586..85389cd 100644
--- a/drivers/gpu/drm/i915/intel_audio.c
+++ b/drivers/gpu/drm/i915/intel_audio.c
@@ -51,10 +51,10 @@
  * related registers. (The notable exception is the power management, not
  * covered here.)
  *
- * The struct i915_audio_component is used to interact between the graphics
- * and audio drivers. The struct i915_audio_component_ops *ops in it is
+ * The struct &i915_audio_component is used to interact between the graphics
+ * and audio drivers. The struct &i915_audio_component_ops @ops in it is
  * defined in graphics driver and called in audio driver. The
- * struct i915_audio_component_audio_ops *audio_ops is called from i915 driver.
+ * struct &i915_audio_component_audio_ops @audio_ops is called from i915 driver.
  */
 
 static const struct {