v4l2videodec: Capture need enqueue frame buffer. Need stop pool flushing.

https://bugzilla.gnome.org/show_bug.cgi?id=752962

UpStream Status: Pending

sys/v4l2/gstv4l2videodec.c

diff --git a/sys/v4l2/gstv4l2videodec.c b/sys/v4l2/gstv4l2videodec.c
index 0d657da..b04c163 100644
--- a/sys/v4l2/gstv4l2videodec.c
+++ b/sys/v4l2/gstv4l2videodec.c
@@ -319,6 +319,7 @@
   /* gst_v4l2_buffer_pool_flush() calls streamon the capture pool and must be
    * called after gst_v4l2_object_unlock_stop() stopped flushing the buffer
    * pool. */
+
   if (self->v4l2capture->pool)
     gst_v4l2_buffer_pool_flush (self->v4l2capture->pool);