avcodec/eatqi: Fix runtime error: signed integer overflow: 4466147 * 1075 cannot be represented in type 'int'

Fixes: 1443/clusterfuzz-testcase-minimized-4826998612426752

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
