Fix ref leak when adding ICE candidates to an SDP

There was a missing decrement to the reference count for the current ICE
candidate when local candidates are being added to an outbound SDP.  This
patch corrects that.



git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/11@374085 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -12198,6 +12198,7 @@ static void add_ice_to_sdp(struct ast_rtp_instance *instance, struct ast_str **a
 		}
 
 		ast_str_append(a_buf, 0, "\r\n");
+		ao2_ref(candidate, -1);
 	}
 
 	ao2_iterator_destroy(&i);