Test_common.make_pif: correct default value of iPv6 param to empty list

Signed-off-by: Gabor Igloi <[email protected]>

Author: gaborigloi

ocaml/xapi/test_common.ml

@@ -154,7 +154,7 @@ let make_pif ~__context ~network ~host ?(device="eth0") ?(mAC="C0:FF:EE:C0:FF:EE
     ?(vLAN=(-1L)) ?(physical=true) ?(ip_configuration_mode=`None) ?(iP="") ?(netmask="")
     ?(gateway="") ?(dNS="") ?(bond_slave_of=Ref.null) ?(vLAN_master_of=Ref.null)
     ?(management=false) ?(other_config=[]) ?(disallow_unplug=false)
-    ?(ipv6_configuration_mode=`None) ?(iPv6=[""]) ?(ipv6_gateway="") ?(primary_address_type=`IPv4) ?(managed=true)
+    ?(ipv6_configuration_mode=`None) ?(iPv6=[]) ?(ipv6_gateway="") ?(primary_address_type=`IPv4) ?(managed=true)
     ?(properties=["gro", "on"]) () =
   Xapi_pif.pool_introduce ~__context
     ~device ~network ~host ~mAC ~mTU ~vLAN ~physical ~ip_configuration_mode