Fixes: signed integer overflow: 8683744 * 256 cannot be represented in type 'int'
Fixes: 23527/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_APE_fuzzer-5679885932822528

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 9f7b252cdf2d0e0f79d16dc7cd575d1884239863)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>