Fix L2Pop mech driver for dvr to handle DVR interface ports

[Vivekanandan Narasimhan]

L2Pop mech driver does not apply L2Pop rules to DVR router interfaces correctly (this might have been caused by competing changes for blueprint ofagent-l2pop)

The patch for this bug will enable DVR Router interface ports to be handled correctly in order to address the network island problem.

Network island is a situation where VMs belonging to two different networks are hosted on two different compute nodes. The compute nodes themselves won't have VMs on the other network except for the one they are hosting.

This fix will enable DVR east-west traffic passthrough for cases where router and its interfaces are added after VMs have already been spawned/active on such routed networks.

[Armando Migliaccio (armando-migliaccio)]

https://review.openstack.org/#/c/112229

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/112229
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=dc658273e7cfe72e50dad40203db8bb0d9bb2188
Submitter: Jenkins
Branch: master

commit dc658273e7cfe72e50dad40203db8bb0d9bb2188
Author: Vivekanandan Narasimhan <email address hidden>
Date: Tue Aug 5 11:36:35 2014 -0700

    Fix to enable L2pop to serve DVR

    This change fixes the information used by the L2pop
    driver to populate l2pop rules that enables DVR to
    route packets across compute servers that have
    tenant VMs that belong to different networks.
    It also fixes the case where VMs were not able to
    obtain IP Addresses when such VMs are on DVR
    hosted subnets.

    Change-Id: Ib630e57c186da60eb15f9ffa6b1b0bfa74f48caa
    Closes-Bug: #1350485
    Closes-Bug: #1352857