[OVN]: fix ovn-db-sync to include gateway chassis

When we sync the SegmentHostMappings with the OVN southbound on start
up, the chassis that are a gateway are being skipped from updating.
The rest of the code base includes those in writing to the
SegmentHostMappings so we should keep those in sync on ovn-db-sync as
well.

Closes-Bug: #2116960
Change-Id: Ie1b375f5c23864d7fa17c9dd05f0453b439835f1
Signed-off-by: Doug Goldstein <cardoe@cardoe.com>

neutron/plugins/ml2/drivers/ovn/mech_driver/ovsdb/ovn_db_sync.py

@@ -1448,7 +1448,7 @@ class OvnSbSynchronizer(OvnDbSynchronizer):
         host_phynets_map = self.ovn_api.get_chassis_hostname_and_physnets()
         current_hosts = set(host_phynets_map)
         previous_hosts = segments_db.get_hosts_mapped_with_segments(
-            ctx, include_agent_types={ovn_const.OVN_CONTROLLER_AGENT})
+            ctx, include_agent_types=set(ovn_const.OVN_CONTROLLER_TYPES))
 
         stale_hosts = previous_hosts - current_hosts
         for host in stale_hosts:

neutron/tests/unit/plugins/ml2/drivers/ovn/mech_driver/ovsdb/test_ovn_db_sync.py

@@ -1241,7 +1241,7 @@ class TestOvnSbSyncML2(test_mech_driver.OVNMechanismDriverTestCase):
                                return_value=hosts_in_neutron) as mock_ghmws:
             ovn_sb_synchronizer.sync_hostname_and_physical_networks(mock.ANY)
             mock_ghmws.assert_called_once_with(
-                mock.ANY, include_agent_types={ovn_const.OVN_CONTROLLER_AGENT})
+                mock.ANY, include_agent_types=set(ovn_const.OVN_CONTROLLER_TYPES))
             all_hosts = set(hostname_with_physnets.keys()) | hosts_in_neutron
             self.assertEqual(
                 len(all_hosts),

releasenotes/notes/ovn-db-sync-gw-agent-cd049668511ac730.yaml

@@ -0,0 +1,7 @@
+---
+fixes:
+  - |
+    ``ovn-db-sync`` skipped chassis that were also gateways for syncing the
+    segment host mappings but all other operations included them so add syncing
+    them to ``ovn-db-sync``. For more information see bug
+    `2116960 <https://bugs.launchpad.net/neutron/+bug/2116960>`_.