avconv: remove redundant handling of async.

Because of a mistake during merging the code for simple and complex
filtergraphs, -async inserts an asyncts filter both on input and output.
Remove the output hunk.

avconv.c

@@ -742,34 +742,6 @@ static int configure_output_audio_filter(FilterGraph *fg, OutputFilter *ofilter,
         pad_idx = 0;
     }
 
-    if (audio_sync_method > 0) {
-        AVFilterContext *async;
-        char args[256];
-        int  len = 0;
-
-        av_log(NULL, AV_LOG_WARNING, "-async has been deprecated. Used the "
-               "asyncts audio filter instead.\n");
-
-        if (audio_sync_method > 1)
-            len += snprintf(args + len, sizeof(args) - len, "compensate=1:"
-                            "max_comp=%d:", audio_sync_method);
-        snprintf(args + len, sizeof(args) - len, "min_delta=%f",
-                 audio_drift_threshold);
-
-        ret = avfilter_graph_create_filter(&async,
-                                           avfilter_get_by_name("asyncts"),
-                                           "async", args, NULL, fg->graph);
-        if (ret < 0)
-            return ret;
-
-        ret = avfilter_link(last_filter, pad_idx, async, 0);
-        if (ret < 0)
-            return ret;
-
-        last_filter = async;
-        pad_idx = 0;
-    }
-
     if ((ret = avfilter_link(last_filter, pad_idx, ofilter->filter, 0)) < 0)
         return ret;