Fix stack trace

bridge_master.py

@@ -595,6 +595,7 @@ def ident():
                 continue
             _callsign = False
             for _peerid in CONFIG['SYSTEMS'][system]['PEERS']:
+                if CONFIG['SYSTEMS'][system]['PEERS'][_peerid]['CALLSIGN']:
                     _callsign = CONFIG['SYSTEMS'][system]['PEERS'][_peerid]['CALLSIGN'].decode()
             if not _callsign:
                 logger.debug("(IDENT) %s System has no peers or no recorded callsign (%s), skipping",system,_callsign)