avidec: Ignore unknown stream types

Improves ticket131

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/avidec.c

@@ -554,8 +554,7 @@ static int avi_read_header(AVFormatContext *s, AVFormatParameters *ap)
                 codec_type = AVMEDIA_TYPE_DATA;
                 break;
             default:
-                av_log(s, AV_LOG_ERROR, "unknown stream type %X\n", tag1);
-                goto fail;
+                av_log(s, AV_LOG_INFO, "unknown stream type %X\n", tag1);
             }
             if(ast->sample_size == 0)
                 st->duration = st->nb_frames;