Fix non-utf prefix for device fields

Author: murrant

LibreNMS/Modules/Os.php

@@ -153,9 +153,11 @@ private function handleChanges(\LibreNMS\OS $os): void
         Log::info(trans('device.attributes.location') . ': ' . $device->location?->display());
         foreach (['hardware', 'version', 'features', 'serial'] as $attribute) {
             if (isset($device->$attribute)) {
-                $device->$attribute = trim($device->$attribute);
+                $device->$attribute = trim(preg_replace('/^[\x00-\x1F\x7F-\xFF]+/', '', $device->$attribute));
+            }
+            if ($device->isDirty($attribute)) {
+                Log::info(DeviceObserver::attributeChangedMessage($attribute, $device->$attribute, $device->getOriginal($attribute)));
             }
-            Log::info(DeviceObserver::attributeChangedMessage($attribute, $device->$attribute, $device->getOriginal($attribute)));
         }
 
         $device->save();