Do not configure l2population mechanism driver when tunneling is not used

[Eugene Nikanorov]

If we configure l2pop driver with vlans, many port-specific processing goes through l2pop mechanism driver.
While this doesn't affect functionality, it leaves different traces in logs including warnings.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/259695

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/259695
Committed: https://git.openstack.org/cgit/openstack/fuel-library/commit/?id=7abe4f807b2d680a530354faf7bd70be7e747988
Submitter: Jenkins
Branch: master

commit 7abe4f807b2d680a530354faf7bd70be7e747988
Author: Sergey Kolekonov <email address hidden>
Date: Sat Dec 19 14:57:58 2015 +0300

    Enable l2population driver only when l2population is enabled

    If L2 population driver is configured along with with vlan segmentation,
    many port-specific processing goes through l2pop mechanism driver, while it
    should not. L2 population mech driver should be disabled along with
    L2 population itself.

    Change-Id: I0c2122a25bd967486412e50c10f18c12ddafddc0
    Closes-bug: #1527601

[Kristina Berezovskaia (kkuznetsova)]

Verify on:
VERSION:
  feature_groups:
    - mirantis
  production: "docker"
  release: "8.0"
  api: "1.0"
  build_number: "478"
  build_id: "478"
  fuel-nailgun_sha: "ae949905142507f2cb446071783731468f34a572"
  python-fuelclient_sha: "4f234669cfe88a9406f4e438b1e1f74f1ef484a5"
  fuel-agent_sha: "481ed135de2cb5060cac3795428625befdd1d814"
  fuel-nailgun-agent_sha: "b2bb466fd5bd92da614cdbd819d6999c510ebfb1"
  astute_sha: "b81577a5b7857c4be8748492bae1dec2fa89b446"
  fuel-library_sha: "420c6fa5f8cb51f3322d95113f783967bde9836e"
  fuel-ostf_sha: "ab5fd151fc6c1aa0b35bc2023631b1f4836ecd61"
  fuel-mirror_sha: "b62f3cce5321fd570c6589bc2684eab994c3f3f2"
  fuelmenu_sha: "fac143f4dfa75785758e72afbdc029693e94ff2b"
  shotgun_sha: "63645dea384a37dde5c01d4f8905566978e5d906"
  network-checker_sha: "9f0ba4577915ce1e77f5dc9c639a5ef66ca45896"
  fuel-upgrade_sha: "616a7490ec7199f69759e97e42f9b97dfc87e85b"
  fuelmain_sha: "6c6b088a3d52dd0eaf43d59f3a3a149c93a07e7e"
(vlan)

Check that parameter l2_population is False in /etc/neutron/plugin.ini. There are no traces in logs