mpegts network_scan: fix problems with having multiple networks

previously as soon as any mux failed it would give up assuming nothing else
could be tuned. However just because no tuner was available that could service
that mux doesn't mean there wasn't one that couldn't service another.

The only real issue I can see with this is if we're idle scanning it's possible
due to bad luck to starve muxes of an attempt. We can either rely on random
chance or put some additional weighting based on time? Though that could be
problematic for other reasons.
httpc: use poll to check for the EINPROGRESS state
tvhcsa_descramble: remove unused elementary_stream parameter
mpegts network_scan: fix problem with active muxes being re-added to scan Q
mpegts network_scan: move scanning structures back to network

This should make things slightly more efficient, I can't remember
now why I made these global in the first place!
mpegts_network: Fix the crash on shutdown (accessing registered but freed timer)
capmt: fix filters and ECM pid check

- EMMs seems work now for modes 3 and 4
descrambler: be more verbose and little fixes
descrambler: small log correction
descrambler: add a timewindow for the odd/even key change
capmt: little optimize the filter
Merge remote-tracking branch 'upstream/master' into durationfilter
mpegts: fix some issues with network scanning

mux matching was far too strict and resulted in a failure to update muxes
with new modulations etc... Also frequency changes were not detected, so
there is some attempt to handle greater changes (mostly just DVB-S, could
be extended).

And where ONID/TSID are set, they are compared as an additional check.
I think it's a case of suck it and see, but on my Astra 28.2E scan this
did a nice job of cleaning up (including tying together modded) muxes.
tsdemux: do not show continuity error in first seconds of streaming

Most hardware stabilizes things after tuning and these messages are
irritating.
capmt: minor fixes (cleanup on socket close)
descrambler: another key-timing fix
mpegts_network_dvb: fix the comment
descrambler: unify log messages, some minor logic changes
Merge remote-tracking branch 'upstream/master' into durationfilter
cwc: return back the key composition - seems like some CA cards returns only single key