The implementation does not support k=32
Fixes: shift exponent 32 is too large for 32-bit type 'unsigned int'
Fixes: 57976/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WAVARC_fuzzer-5911925807775744
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 40cec0b465)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>