Provide fallback for disabled port security extension
Provide fallback for disabled port security extension

The push notification logic always assumed the port security object
would exist but it is not present on the port when the extension is
disabled. This defaults it to true like the server side code.[1]

1.
https://github.com/openstack/neutron/blob/c430e9b8d41c139284e840be37629afcdbc96b37/neutron/plugins/ml2/rpc.py#L142

Change-Id: Ice89ad9dd486ad5fcac534ef5f7d8aae3b6b0f97
Closes-Bug: #1694420

openstack/neutron,huntxu/neutron,mahak/neutron,openstack/neutron,eayunstack/neutron,mahak/neutron,mahak/neutron,noironetworks/neutron,huntxu/neutron,openstack/neutron,eayunstack/neutron,noironetworks/neutron