This should reduces the number of uninteresting timeouts encountered

A single threshold for all codecs did not work

Fixes: 13979/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_QTRLE_fuzzer-5629872380051456 (14sec -> 4sec)
Fixes: 14709/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_GDV_fuzzer-5704215281795072 (179sec -> 7sec)
Fixes: 16296/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_HNM4_VIDEO_fuzzer-5756304521428992 (108sec -> 9sec)
Fixes: 15620/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_GIF_fuzzer-5657214435459072 (26sec -> 26ms)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>