Show the "service" XML element whenever a tunnel is detected.

Previously this would be omitted if the service was not otherwise
discovered, and the port it was on was not in nmap-services. (There was
not problem if the port was present in nmap-services with a name of
"unknown".)

CHANGELOG

@@ -1,5 +1,9 @@
 # Nmap Changelog ($Id$); -*-text-*-
 
+o Changed XML output to show the "service" element whenever a tunnel
+  is discovered for a port, even if the service behind it was unknown.
+  [Matt Foster]
+
 o [Zenmap] Fixed a crash that would happen in the profile editor when
   the script.db file doesn't exist. The bug was reported by Daniel
   Miller.

output.cc

@@ -778,7 +778,7 @@ void printportoutput(Target *currenths, PortList *plist) {
           xml_attribute("reason_ip", "%s", inet_ntop_ez(&current->reason.ip_addr, sizeof(current->reason.ip_addr)));
         xml_close_empty_tag();
 
-        if (sd.name || sd.service_fp)
+        if (sd.name || sd.service_fp || sd.service_tunnel != SERVICE_TUNNEL_NONE)
           print_xml_service(&sd);
 
         rowno++;