Bug#1042395: casparcg-server FTBFS with FFmpeg 6

[Adrian Bunk <bunk@debian.org>]

Source: casparcg-server
Version: 2.3.3+dfsg-3
Severity: serious
Tags: ftbfs trixie sid

https://buildd.debian.org/status/logs.php?pkg=casparcg-server&ver=2.3.3%2Bdfsg-3%2Bb2

...
/<<PKGBUILDDIR>>/src/modules/ffmpeg/producer/av_producer.cpp: In constructor ‘caspar::ffmpeg::Decoder::Decoder(AVStream*)’:
/<<PKGBUILDDIR>>/src/modules/ffmpeg/producer/av_producer.cpp:109:35: error: ‘AV_CODEC_CAP_AUTO_THREADS’ was not declared in this scope; did you mean ‘AV_CODEC_CAP_FRAME_THREADS’?
  109 |         if (codec->capabilities & AV_CODEC_CAP_AUTO_THREADS) {
      |                                   ^~~~~~~~~~~~~~~~~~~~~~~~~
      |                                   AV_CODEC_CAP_FRAME_THREADS
...