lavfi/af_adeclick: fix double free after ff_filter_frame fail

ff_filter_frame fail will free the frame, so we just returen after this
function fail.

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Jun Zhao <barryjzhao@tencent.com>

libavfilter/af_adeclick.c

@@ -592,7 +592,7 @@ static int filter_frame(AVFilterLink *inlink)
 
     ret = ff_filter_frame(outlink, out);
     if (ret < 0)
-        goto fail;
+        return ret;
 
     if (s->samples_left > 0) {
         s->samples_left -= s->hop_size;