Adds audio support for input YPbPr, AV and S-Video on Mygica X8507 card.

Remains to be done: IR, FM and ISDBT
Signed-off-by: NAlfredo J. Delaiti <alfredodelaiti@netscape.net>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>