introspection: add missing allow-none annotations

https://bugzilla.gnome.org/show_bug.cgi?id=730952

gst/rtsp-server/rtsp-client.c

@@ -3015,7 +3015,8 @@ gst_rtsp_client_handle_message (GstRTSPClient * client,
 /**
  * gst_rtsp_client_send_message:
  * @client: a #GstRTSPClient
- * @session: (transfer none): a #GstRTSPSession to send the message to or %NULL
+ * @session: (allow-none) (transfer none): a #GstRTSPSession to send
+ *   the message to or %NULL
  * @message: (transfer none): The #GstRTSPMessage to send
  *
  * Send a message message to the remote end. @message must be a

gst/rtsp-server/rtsp-media.c

@@ -2217,7 +2217,8 @@ no_rtpbin:
 /**
  * gst_rtsp_media_prepare:
  * @media: a #GstRTSPMedia
- * @thread: (transfer full): a #GstRTSPThread to run the bus handler or %NULL
+ * @thread: (transfer full) (allow-none): a #GstRTSPThread to run the
+ *   bus handler or %NULL
  *
  * Prepare @media for streaming. This function will create the objects
  * to manage the streaming. A pipeline must have been set on @media with
@@ -2572,7 +2573,7 @@ not_prepared:
 /**
  * gst_rtsp_media_get_time_provider:
  * @media: a #GstRTSPMedia
- * @address: an address or %NULL
+ * @address: (allow-none): an address or %NULL
  * @port: a port or 0
  *
  * Get the #GstNetTimeProvider for the clock used by @media. The time provider

gst/rtsp-server/rtsp-mount-points.c

@@ -221,7 +221,7 @@ has_prefix (DataItem * str, DataItem * prefix)
  * gst_rtsp_mount_points_match:
  * @mounts: a #GstRTSPMountPoints
  * @path: a mount point
- * @matched: (out): the amount of @path matched
+ * @matched: (out) (allow-none): the amount of @path matched
  *
  * Find the factory in @mounts that has the longest match with @path.
  *