Improvement for matching LLDP neighbors with known hosts. (#11445)

* Minor addition to find_device_id, such that we match LLDP hosts presenting with FQDN with devices where $hostname + $config['mydomain'] is a match.
This yields clickable links in the neighbor overview.

* Modified to comply with comments in code review

includes/discovery/functions.inc.php

@@ -1369,6 +1369,10 @@ function find_device_id($name = '', $ip = '', $mac_address = '')
         if ($mydomain = Config::get('mydomain')) {
             $where[] = '`hostname`=?';
             $params[] = "$name.$mydomain";
+
+            $where[] = 'concat(`hostname`, \'.\', ?) =?';
+            $params[] = "$mydomain";
+            $params[] = "$name";
         }
     }