Add Serialnumber for some Dell ForceTen devices (#12960)

* Add Serialnumber for some Dell Force devices

* Also in entity-physical

* fix style

* fix style

* add testdata

includes/definitions/discovery/dnos.yaml

@@ -27,6 +27,7 @@ modules:
             - Dell-Vendor-MIB::productIdentificationVersion.0
             - DELL-NETWORKING-CHASSIS-MIB::dellNetStackUnitCodeVersion.1
         serial:
+            - Dell-Vendor-MIB::productIdentificationServiceTag.1
             - Dell-Vendor-MIB::productIdentificationSerialNumber.0
             - DELL-NETWORKING-CHASSIS-MIB::dellNetStackUnitSerialNumber.1
     processors:

includes/discovery/entity-physical/entity-physical.inc.php

@@ -117,6 +117,7 @@ if ($device['os'] == 'saf-cfm') {
         }
     }
 }
+
 if ($device['os'] == 'ios' or $device['os'] == 'iosxe') {
     $tables = [
         ['num_oid' => '.1.3.6.1.4.1.9.9.661.1.3.1.1.1.', 'oid' => 'c3gImsi',  'state_name' => 'c3gImsi',  'mib' => 'CISCO-WAN-3G-MIB', 'descr' => 'IMSI',  'entPhysicalIndex' => '9999'],
@@ -250,6 +251,10 @@ foreach ($entity_array as $entPhysicalIndex => $entry) {
         $entPhysicalAssetID = array_key_exists('entPhysicalAssetID', $entry) ? $entry['entPhysicalAssetID'] : '';
     }//end if
 
+    if ($device['os'] == 'dnos' && $entPhysicalSerialNum == 'NA' && preg_match('/Unit/', $entPhysicalName)) {
+        $entPhysicalSerialNum = snmp_get($device, '.1.3.6.1.4.1.674.10895.3000.1.2.100.8.1.4.' . preg_replace('/Unit (\d+)/', '$1', $entPhysicalName), '-Oqv', '');
+    }
+
     if (isset($entity_array[$entPhysicalIndex]['0']['entAliasMappingIdentifier'])) {
         $ifIndex = $entity_array[$entPhysicalIndex]['0']['entAliasMappingIdentifier'];
         if (! strpos($ifIndex, 'fIndex') || $ifIndex == '') {