avcodec/mp3_header_decompress_bsf: Check sample_rate_index

Fixes: out of array read
Fixes: 19309/clusterfuzz-testcase-minimized-ffmpeg_BSF_MP3_HEADER_DECOMPRESS_fuzzer-5651002950942720

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit f064c7c449)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavcodec/mp3_header_decompress_bsf.c

@@ -62,6 +62,11 @@ static int mp3_header_decompress(AVBSFContext *ctx, AVPacket *out)
     lsf     = sample_rate < (24000+32000)/2;
     mpeg25  = sample_rate < (12000+16000)/2;
     sample_rate_index= (header>>10)&3;
+    if (sample_rate_index == 3) {
+        ret = AVERROR_INVALIDDATA;
+        goto fail;
+    }
+
     sample_rate= avpriv_mpa_freq_tab[sample_rate_index] >> (lsf + mpeg25); //in case sample rate is a little off
 
     for(bitrate_index=2; bitrate_index<30; bitrate_index++){