[media] media-entity.h: Document some ancillary functions

Add a basic documentation for most ancillary functions.

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
This commit is contained in:
Mauro Carvalho Chehab 2015-12-13 08:20:46 -02:00
commit 60266185d7