lnkServerToVolume marked as a link in the datamodel

git-svn-id: http://svn.code.sf.net/p/itop/code/trunk@2563 a333f486-631f-4898-b8df-5754b55c2be0

datamodels/2.x/itop-storage-mgmt/datamodel.itop-storage-mgmt.xml

@@ -1523,6 +1523,7 @@
     <class id="lnkServerToVolume" _delta="define">
       <parent>cmdbAbstractObject</parent>
       <properties>
+        <is_link>1</is_link>
         <category>bizmodel,configmgmt</category>
         <abstract>false</abstract>
         <key_type>autoincrement</key_type>