Do not return a probe score from set_codec_from_probe_data() if the codec was ignored.

This is a workaround for the issue that stream probing can use
the score of another codec type for mpeg stream autodetection.
Fixes ticket #3821.

libavformat/utils.c

@@ -278,11 +278,11 @@ static int set_codec_from_probe_data(AVFormatContext *s, AVStream *st,
             if (!strcmp(fmt->name, fmt_id_type[i].name)) {
                 st->codec->codec_id   = fmt_id_type[i].id;
                 st->codec->codec_type = fmt_id_type[i].type;
-                break;
+                return score;
             }
         }
     }
-    return score;
+    return 0;
 }
 
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