Fixed devices state filter when state = 0 (#9277)

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html/includes/table/devices.inc.php

@@ -73,7 +73,7 @@ if (!empty($vars['type'])) {
     }
 }
 
-if (!empty($vars['state'])) {
+if (isset($vars['state']) && $vars['state'] !== "") {
     $sql .= ' AND status= ?';
     if (is_numeric($vars['state'])) {
         $param[] = $vars['state'];