tools/target_dec_fuzzer: Adjust threshold for smacker audio

Fixes: Timeout
Fixes: 47043/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SMACKAUD_fuzzer-4824799337119744

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

tools/target_dec_fuzzer.c

@@ -256,6 +256,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
     case AV_CODEC_ID_SANM:        maxpixels  /= 16;    break;
     case AV_CODEC_ID_SCPR:        maxpixels  /= 32;    break;
     case AV_CODEC_ID_SCREENPRESSO:maxpixels  /= 64;    break;
+    case AV_CODEC_ID_SMACKAUDIO:  maxsamples /= 4096;  break;
     case AV_CODEC_ID_SMACKVIDEO:  maxpixels  /= 64;    break;
     case AV_CODEC_ID_SNOW:        maxpixels  /= 128;   break;
     case AV_CODEC_ID_TARGA:       maxpixels  /= 128;   break;