drm/doc: Appease sphinx

Mostly this is unexpected indents. But really it's just a
demonstration for my patch, all these issues have been found&fixed
using the correct source file and line number support I just added.
All line numbers have been perfectly accurate.

One issue looked a bit fishy in intel_lrc.c, where I don't quite grok
what sphinx is unhappy about. But since that file looks like it has
never seen a proper kernel-doc parser I figured better to fix in a
separate path.

v2: Use fancy new &drm_device->struct_mutex linking (Jani).

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: linux-doc@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
diff --git a/drivers/gpu/drm/drm_plane_helper.c b/drivers/gpu/drm/drm_plane_helper.c
index 369d2898..fc51306 100644
--- a/drivers/gpu/drm/drm_plane_helper.c
+++ b/drivers/gpu/drm/drm_plane_helper.c
@@ -219,10 +219,12 @@
  *
  * Note that we make some assumptions about hardware limitations that may not be
  * true for all hardware --
- *   1) Primary plane cannot be repositioned.
- *   2) Primary plane cannot be scaled.
- *   3) Primary plane must cover the entire CRTC.
- *   4) Subpixel positioning is not supported.
+ *
+ * 1. Primary plane cannot be repositioned.
+ * 2. Primary plane cannot be scaled.
+ * 3. Primary plane must cover the entire CRTC.
+ * 4. Subpixel positioning is not supported.
+ *
  * Drivers for hardware that don't have these restrictions can provide their
  * own implementation rather than using this helper.
  *