[media] add documentation for struct dvb_tuner_info
[media] add documentation for struct dvb_tuner_info

Despite being used everywhere at DVB frontends, the
struct dvb_tuner_info were never documented.

Signed-off-by: Mauro Carvalho Chehab <ad86ba2154032c9f55743a190faa2459a9d61d42@osg.samsung.com>
Acked-by: Jonathan Corbet <b2ce64d5587c02f12e367eac59751145a0660c51@lwn.net>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs