Most common case would be DVB-C / DVB-T combination cards.
Cards with multiple delivery systems are only supported
starting from DVBv5 API (Kernel 2.6.38).
In this case, we loop over all delivery systems and
just treat them as different cards would be treated:
They all get their own TUNER-type, channel-list parsing etc.
If VDR-channel-config is used, we know the service_id.
Using that, PMT can be extracted from PAT (code for that
inspired by szap-s2 again).
For this, we need to demux PAT with a special filter-setup,
and once PMT was found it can be added to the PID-list.
PMT is only resolved the first time one tunes to a channel,
then stored in the channel-list in memory.
With PMT available, ffmpeg can safely decode the teletext-pids.
Now also "stream ID" (for DVB-S2) and "inversion" are understood.
The parameter-string can also provide information on FEC, rolloff etc. For DVB-S, "auto" which mpv uses by default should be fine, I can also confirm it works. For non-DVB-S cards, it might be useful to also parse this information in case of a vdr-channel list.
As I have no such hardware and thus would have to do it blindly, I added a FIXME.
Mostly complete vdr-channels.conf format documentation is at http://www.vdr-wiki.de/wiki/index.php/Channels.conf (german only).
It contains now also a boolean which tells whether this is an DVB-S2 channel (not initialized yet - tbd in next commit).
We could also pass through the type of the delivery system (would be more flexible), but the delivery-system-enum is only available with S2API, so this is more backwards-compatible.
If someone has DVB-T2 / DVB-C2 hardware and extends the code to deal with it, this should be changed.
