neutron-dynamic-routing now works with OVN

With [0] the incompatibility between neutron-dynamic-routing and OVN has
been removed. Mark the BGP extensions as supported by OVN and amend the
list of gaps accordingly.

[0] https://review.opendev.org/c/openstack/neutron/+/864051

Change-Id: I773e581e8d044e87e45a10394cca25ecbe7603ad

doc/source/ovn/gaps.rst

@@ -8,12 +8,6 @@ It is not a complete list, but is enough to be used as a starting point for
 implementors working on closing these gaps. A TODO list for OVN is located
 at [1]_.
 
-* BGP support
-
-  Neutron-dynamic-routing supports making a tenant subnet routable via BGP, and
-  can announce host routes for both floating and fixed IP addresses. These
-  functions are not supported in OVN.
-
 * Baremetal provisioning with iPXE without Neutron DHCP agent for IPv6
 
   The core OVN built-in DHCP server implementation does not

neutron/common/ovn/extensions.py

@@ -17,6 +17,9 @@
 from neutron_lib.api.definitions import allowedaddresspairs
 from neutron_lib.api.definitions import auto_allocated_topology
 from neutron_lib.api.definitions import availability_zone as az_def
+from neutron_lib.api.definitions import bgp
+from neutron_lib.api.definitions import bgp_4byte_asn
+from neutron_lib.api.definitions import bgp_dragentscheduler
 from neutron_lib.api.definitions import default_subnetpools
 from neutron_lib.api.definitions import dns
 from neutron_lib.api.definitions import dns_domain_keywords
@@ -161,4 +164,7 @@
     logging.ALIAS,
     vpn.ALIAS,
     vpn_endpoint_groups.ALIAS,
+    bgp.ALIAS,
+    bgp_4byte_asn.ALIAS,
+    bgp_dragentscheduler.ALIAS,
 ]