Update opencore-amr libraries
Update Opus to 1.1rc2
Update libspeex to a recent build
Update build instructions for thirdparty libs
Update ffmpeg

Also re-enable --disable-doc, which was broken for a while.
Make sure side-data is merged until a proper solution is implemented
Disable the HQ Deint option on XP, to reduce user confusion
Update ffmpeg for matroska enhancements
Handle sample skips in the audio decoder

This is used by opus to drop pre-skip samples.
Fix timestamp resync after recent changes
Remove XP hint from tooltip, the option is now disabled there.
Update ffmpeg for DiscardPadding support
avcodec: use active_thread_type to check if mt decoding is active
Update ffmpeg
avcodec: remove thread config table

Instead simply enable MT decoding on all codecs, except MPEG4 (until it
can be re-evaluated)
avcodec: simplify timestamp logic selection by using codec property
avcodec: simplify video decode loop, video decoders consume the full buffer by default
avcodec: remove now unused variable
Suppress invalid mp1/2/3 streams
dxva2: Fix and enable VC-1/WMV3 decoding on Intel