avcodec/aacenc: Fix sample rate check

Fixes out of array read
Fixes CID1257803, CID1257797, CID1257789, CID1257786
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/aacenc.c

@@ -740,7 +740,7 @@ static av_cold int aac_encode_init(AVCodecContext *avctx)
 
     s->channels = avctx->channels;
 
-    ERROR_IF(i == 16,
+    ERROR_IF(i >= 12,
              "Unsupported sample rate %d\n", avctx->sample_rate);
     ERROR_IF(s->channels > AAC_MAX_CHANNELS,
              "Unsupported number of channels: %d\n", s->channels);