Doxygen addition

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@150051 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -1397,7 +1397,7 @@ struct sip_pvt {
 							you know more) */
 	struct sip_st_dlg *stimer;		/*!< SIP Session-Timers */              
   
-	int red; 
+	int red; 				/*!< T.140 RTP Redundancy */
 
 	struct sip_subscription_mwi *mwi;       /*!< If this is a subscription MWI dialog, to which subscription */
 };