[media] v4l2-async: document the remaining stuff

There are one enum and 4 functions undocumented there.
Document them. That will fix the broken links at the
v4l2-subdev.rst file.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Mauro Carvalho Chehab 2016-07-21 09:24:55 -03:00
commit ab4f5a4afc