Don't count guest logins as authenticated connections...

When enforcing the MaxConcurrentConnections limit, don't count connections for user's with blank passwords (i.e. Guest) as authenticated.

src/sbbs3/main.cpp

@@ -4483,7 +4483,8 @@ void node_thread(void* arg)
 	if(sbbs->answer()) {
 
 		login_success = true;
-		listAddNodeData(&current_logins, sbbs->client.addr, strlen(sbbs->client.addr)+1, sbbs->cfg.node_num, LAST_NODE);
+		if(sbbs->useron.pass[0])
+			listAddNodeData(&current_logins, sbbs->client.addr, strlen(sbbs->client.addr)+1, sbbs->cfg.node_num, LAST_NODE);
 		if(sbbs->sys_status&SS_QWKLOGON) {
 			sbbs->getsmsg(sbbs->useron.number);
 			sbbs->qwk_sec();