avformat/rmdec: Use 64bit for intermediate for DEINT_ID_INT4
Fixes: runtime error: signed integer overflow: 65312 * 65535 cannot be represented in type 'int'
Fixes: 32832/clusterfuzz-testcase-minimized-ffmpeg_dem_RM_fuzzer-
4817710040088576
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
e2c2872393f25253aa40861a9707934c4b83a3af)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>