neutron-fwaas has become active again

Depends-On: https://review.opendev.org/c/openstack/kolla/+/914855

Change-Id: Ie5a7b2da9a351e8f47a1ae830bb2fee0a8e35e38

Depends-On: I561504160e5548c54d1af31821c3366ab34cf0ec
Change-Id: I15e5c0e0a956ee181873cf002229532a15ff959d
Co-Authored-By: jacky06 <zhang.min@99cloud.net>

If we are not using l3 ha mode, it’s not necessary to delete the namespaces related to l3. It will speed up the start of the neutron l3 agent.

Change-Id: I78f6d927a78e8f9e4ed855e4b6d1362bdfc6b985
Closes-Bug: #1785880

As neutron-vpnaas-agent has been loaded just inside of the existing l3 agent
rather than requiring operators to run a completely different binary with a
subclass of the existing L3 agent[1]. We need restructure this role to fit
with this new feature.

[1] https://review.openstack.org/488247

Depends-On: I47cd8ba5a14da3c76d5b1eb0b4c0cf0c729eb2ff
Change-Id: Id690a652bc9facf1c3e39358f548ab7ddd967d80
Implements: blueprint restructure-neutron-vpnaas
Closes-Bug: #1731498

Remove all l3 related namespaces in case of multiple active routers in
l3 high available mode. The root cause is that keepalived does not
remove the vip address from nic during starting.

neutron-vpnaas-agent is subclass of l3 agent, so should remove all l3
related namespace before starting vpnaas agent.

Closes-Bug: #1703078
Depends-On: Ic9417d2eb03e0dd93f7c668b189b4ad9c72eae0f
Change-Id: I05c1faf2551bb5e70c299e884adf58cd2af52739