Remove unused variable

cloud/rax_clb

@@ -141,7 +141,6 @@ def to_dict(obj):
     for key in dir(obj):
         value = getattr(obj, key)
         if key == 'virtual_ips':
-            virtual_ips = []
             instance[key] = []
             for vip in value:
                 vip_dict = {}