gst/: Update for GST_FOURCC_FORMAT API change.
Original commit message from CVS: * gst/asfdemux/gstasfdemux.c: (gst_asf_demux_add_video_stream): * gst/realmedia/rmdemux.c: (gst_rmdemux_chain), (gst_rmdemux_add_stream), (gst_rmdemux_parse_mdpr): Update for GST_FOURCC_FORMAT API change.