monitoring: Rearrange code in the HostgroupQuery

refs #9956

modules/monitoring/library/Monitoring/Backend/Ido/Query/HostgroupQuery.php

@@ -27,9 +27,6 @@ class HostgroupQuery extends IdoQuery
      * {@inheritdoc}
      */
     protected $columnMap = array(
-        'instances' => array(
-            'instance_name' => 'i.instance_name'
-        ),
         'hostgroups' => array(
             'hostgroup'         => 'hgo.name1 COLLATE latin1_general_ci',
             'hostgroup_alias'   => 'hg.alias COLLATE latin1_general_ci',
@@ -43,6 +40,9 @@ class HostgroupQuery extends IdoQuery
             'host_alias'            => 'h.alias',
             'host_display_name'     => 'h.display_name COLLATE latin1_general_ci',
         ),
+        'instances' => array(
+            'instance_name' => 'i.instance_name'
+        ),
         'servicegroups' => array(
             'servicegroup'          => 'sgo.name1 COLLATE latin1_general_ci',
             'servicegroup_alias'    => 'sg.alias COLLATE latin1_general_ci',
@@ -101,6 +101,18 @@ class HostgroupQuery extends IdoQuery
         );
     }
 
+    /**
+     * Join instances
+     */
+    protected function joinInstances()
+    {
+        $this->select->join(
+            array('i' => $this->prefix . 'instances'),
+            'i.instance_id = hg.instance_id',
+            array()
+        );
+    }
+
     /**
      * Join service groups
      */
@@ -138,16 +150,4 @@ class HostgroupQuery extends IdoQuery
             array()
         );
     }
-
-    /**
-     * Join instances
-     */
-    protected function joinInstances()
-    {
-        $this->select->join(
-            array('i' => $this->prefix . 'instances'),
-            'i.instance_id = hg.instance_id',
-            array()
-        );
-    }
 }