fix linstor manager deflate

Author: Wescoeur

drivers/linstor-manager

@@ -597,7 +597,7 @@ def repair(session, args):
 
 def deflate(session, args):
     try:
-        cowutil = getCowUtil(args['vdiType'])
+        vdi_type = args['vdiType']
         device_path = args['devicePath']
         new_size = int(args['newSize'])
         old_size = int(args['oldSize'])
@@ -609,7 +609,7 @@ def deflate(session, args):
             group_name,
             logger=util.SMlog
         )
-        LinstorCowUtil(session, linstor, cowutil).deflate(device_path, new_size, old_size, zeroize)
+        LinstorCowUtil(session, linstor, vdi_type).deflate(device_path, new_size, old_size, zeroize)
         return ''
     except Exception as e:
         util.SMlog('linstor-manager:deflate error: {}'.format(e))