Fixes: signed integer overflow: 2147483647 + 1 cannot be represented in type 'int'
Fixes: 9291/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_DIRAC_fuzzer-6324345860259840
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 462d1be6dec5ff4768be8c202f359cbf037db3c6)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>