fix(neutron): read physical_network from port binding if able

If we are able to read the physical_network from the port binding
information then we should do that over looking it up.

Uses: https://review.opendev.org/c/openstack/ironic/+/964570

Author: cardoe

python/neutron-understack/neutron_understack/neutron_understack_mech.py

@@ -3,6 +3,7 @@
 
 from neutron_lib import constants as p_const
 from neutron_lib.api.definitions import portbindings
+from neutron_lib.api.definitions import segment as seg_def
 from neutron_lib.callbacks import events
 from neutron_lib.callbacks import registry
 from neutron_lib.callbacks import resources
@@ -115,16 +116,18 @@ def _update_port_baremetal(self, context: PortContext) -> None:
         current_vif_other = context.vif_type == portbindings.VIF_TYPE_OTHER
 
         if current_vif_unbound and original_vif_other:
-            local_link_info = utils.local_link_from_binding_profile(
-                context.original[portbindings.PROFILE]
-            )
+            port = context.original
         else:
-            local_link_info = utils.local_link_from_binding_profile(
-                context.current[portbindings.PROFILE]
-            )
-        vlan_group_name = self.ironic_client.baremetal_port_physical_network(
-            local_link_info
+            port = context.current
+
+        local_link_info = utils.local_link_from_binding_profile(
+            port[portbindings.PROFILE]
         )
+        vlan_group_name = port[portbindings.PROFILE].get(seg_def.PHYSICAL_NETWORK)
+        if vlan_group_name is None and local_link_info is not None:
+            vlan_group_name = self.ironic_client.baremetal_port_physical_network(
+                local_link_info
+            )
 
         if current_vif_unbound and original_vif_other:
             self._tenant_network_port_cleanup(context)