* DV demuxer is now capable of decoding auxilary audio stream. So,
     everybody who still uses second streo track for dubbing can
     now export it.

   * void* -> DVDemuxContext* change (per Fabrice's suggestion).

   * -dv1394 capture now works in all modes.


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@2458 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b