The v4l2_subdev reference was using the wrong tag. Fix it.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Entities are represented by a :c:type:`struct media_entity <media_entity>`
instance, defined in ``include/media/media-entity.h``. The structure is usually
embedded into a higher-level structure, such as
-:ref:`v4l2_subdev` or :ref:`video_device`
+:c:type:`v4l2_subdev` or :c:type:`video_device`
instances, although drivers can allocate entities directly.
Drivers initialize entity pads by calling