avcodec/dstdec: Replace AC overread check by sample rate check

Real files do skip coding 0 bits at the end, thus this kind of check
does not work reliable.

Fixes: Ticket 8770
Fixes: dst-256fs44-6ch-refdstencoder.dff

The samplerate is specified in ISO/IEC 14496-3:2005(E) as one of 3 fixed
values, this also can be used to limit the duration and avoid the timeout

This reverts commit f6df99db.

(cherry picked from commit 1679f23b)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavcodec/dstdec.c

@@ -85,6 +85,12 @@ static av_cold int decode_init(AVCodecContext *avctx)
         return AVERROR_PATCHWELCOME;
     }
 
+    // the sample rate is only allowed to be 64,128,256 * 44100 by ISO/IEC 14496-3:2005(E)
+    // We are a bit more tolerant here, but this check is needed to bound the size and duration
+    if (avctx->sample_rate > 512 * 44100)
+        return AVERROR_INVALIDDATA;
+
+
     if (DST_SAMPLES_PER_FRAME(avctx->sample_rate) & 7) {
         return AVERROR_PATCHWELCOME;
     }