Comment 10 for bug 1564335

Ip from auto-addressed subnets can not be deleted durig update_port workflow because of [1].
Even if this area was significantly reworked during liberty, the same behavior is preserved at least from kilo [2].
So if ip address is not present in updated 'fixed_ips', ip address is not removed for auto-addressed subnet case.

One way to allow removing ip for auto-addressed subnets is to add additional parameter to update_port, that changes behavior and allows to remove ips for auto-addressed subnets.

Is it ok to fix it that way?

[1] https://github.com/openstack/neutron/blob/f494de47fcef7776f7d29d5ceb2cc4db96bd1efd/neutron/db/ipam_backend_mixin.py#L435
[2] https://github.com/openstack/neutron/blob/stable/kilo/neutron/db/db_base_plugin_v2.py#L444