Switch to use test_utils.call_until_true

test.call_until_true has been deprecated since Newton on Tempest side,
and now Tempest provides test_utils.call_until_true as the stable
library method. So this patch switches to use the stable method before
removing old test.call_until_true on Tempest side.

Change-Id: I139b2ceeb9f840362ae4eeb06d391af4c83733ab
diff --git a/neutron/tests/tempest/api/test_network_ip_availability.py b/neutron/tests/tempest/api/test_network_ip_availability.py
index 324c3fd..b3f2182 100644
--- a/neutron/tests/tempest/api/test_network_ip_availability.py
+++ b/neutron/tests/tempest/api/test_network_ip_availability.py
@@ -16,6 +16,7 @@
 import netaddr
 
 from tempest.lib.common.utils import data_utils
+from tempest.lib.common.utils import test_utils
 from tempest.lib import exceptions as lib_exc
 from tempest import test
 
@@ -154,7 +155,7 @@
             return used_ip - 1 == used_ip_after_port_delete
 
         self.assertTrue(
-            test.call_until_true(
+            test_utils.call_until_true(
                 get_net_availability, DELETE_TIMEOUT, DELETE_SLEEP),
             msg="IP address did not become available after port delete")