udpsrc: fix typo in documentation
https://bugzilla.gnome.org/show_bug.cgi?id=792458
diff --git a/gst/udp/gstudpsrc.c b/gst/udp/gstudpsrc.c
index 1f77251..fdeca5d 100644
--- a/gst/udp/gstudpsrc.c
+++ b/gst/udp/gstudpsrc.c
@@ -57,7 +57,7 @@
* off proprietary header, for example.
*
* The udpsrc is always a live source. It does however not provide a #GstClock,
- * this is left for upstream elements such as an RTP session manager or demuxer
+ * this is left for downstream elements such as an RTP session manager or demuxer
* (such as an MPEG demuxer). As with all live sources, the captured buffers
* will have their timestamp set to the current running time of the pipeline.
*
