Grandstream basic support (#9906)

* grandstream simple discovery

* grandstream simple discovery tests

* exclusion in linux matching

* Revert un-necessary changes, and change "over:" to ping

includes/definitions/grandstream-ht.yaml

@@ -0,0 +1,15 @@
+os: grandstream-ht
+group: grandstream
+text: 'Grandstream HT'
+type: network
+icon: grandstream
+over:
+    - { graph: device_ping_perf, text: 'Ping Response' }
+mib_dir:
+    - grandstream
+discovery:
+    -
+      sysObjectID:
+        - .1.3.6.1.4.1.8072.3.2.10
+      sysDescr_regex:
+        - '/^Linux HT/'

includes/polling/os/grandstream-ht.inc.php

@@ -0,0 +1,12 @@
+<?php
+// Grandstream HT
+$oids = [
+    'serial' => '.1.3.6.1.4.1.42397.1.2.1.0.0',
+    'versionCore' => '.1.3.6.1.4.1.42397.1.2.3.2.0.0',
+    'versionBase' => '.1.3.6.1.4.1.42397.1.2.3.3.0.0'
+];
+$os_data = snmp_get_multi_oid($device, $oids);
+foreach ($oids as $var => $oid) {
+    $$var = $os_data[$oid];
+}
+$version = 'Core: ' . $versionCore . ', Base: ' . $versionBase;