Provide correct fip cidr when deleting port forwarding

The second parameter of fip_id_cidrs requires a cidr, but now is address. this
causes function `_sync_and_remove_fip` fail to remove vip as expected.

if current is ha router, in function _sync_and_remove_fip will call
`ri._remove_vip(fip_id_cidr[1])`. the final parameter is passed to
KeepalivedInstance.remove_vip_by_ip_address and compare with attribute vips.
the values of vips are of type CIDR.

if not ha, the following process processing use netaddr.IPNetwork and can be
performed as expected.

Closes-bug: #1873708

Change-Id: I2ae2ade29700a56dc340256389bf8b0efd697ba4

neutron/agent/l3/extensions/port_forwarding.py

@@ -344,8 +344,8 @@ class PortForwardingAgentExtension(l3_extension.L3AgentExtension):
         iptables_manager.apply()
 
         fip_id_cidrs = set([(pf.floatingip_id,
-                             str(pf.floating_ip_address)) for pf in
-                            port_forwardings])
+                             str(netaddr.IPNetwork(pf.floating_ip_address)))
+                            for pf in port_forwardings])
         self._sync_and_remove_fip(context, fip_id_cidrs, device, ri)
         self._store_local(port_forwardings, events.DELETED)
 

neutron/tests/unit/agent/l3/extensions/test_port_forwarding.py

@@ -14,6 +14,7 @@
 #    under the License.
 
 import mock
+import netaddr
 from neutron_lib import constants as lib_const
 from neutron_lib import context
 from oslo_utils import uuidutils
@@ -274,7 +275,7 @@ class FipPortForwardingExtensionTestCase(PortForwardingExtensionBaseTestCase):
             self.portforwarding1.external_port,
             protocol=self.portforwarding1.protocol)
         mock_device.delete_addr_and_conntrack_state.assert_called_once_with(
-            str(self.portforwarding1.floating_ip_address))
+            str(netaddr.IPNetwork(self.portforwarding1.floating_ip_address)))
         fip_status = {
             self.portforwarding1.floatingip_id:
                 lib_const.FLOATINGIP_STATUS_DOWN}