Only try to auto-detect LATM in mpegts if the LOAS demuxer was configured.

This allows to decode LATM-in-mpegts without the LOAS demuxer.
matroskaenc: add codec_tag lists back.

This reverts 312645e :
"Do not set codec_tag property for matroska muxers."

Also adds dummy codec_tag lists with codecs
supported in mkv but not in wav / avi.

Fixes ticket #2169.
ff_mss12_decode_init: check dimensions

Fixes assertion failure

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>