quickstart shall allow to pass empty external networks for undercloud

[Yolanda Robla]

On my previous deployments, i had undercloud networks defined like that: undercloud_networks: {}

This currently fails, because it's assuming that we always have some value, and is checking for a device type, failing with: "AnsibleUndefinedVariable: 'dict object' has no attribute 'device_type'"

This is because the code doesn't check for an empty value there. Template needs to be fixed to support it

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/508881

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/508881
Committed: https://git.openstack.org/cgit/openstack/tripleo-quickstart-extras/commit/?id=580c8ab5438e18e8224a81362a467f2f37fae86e
Submitter: Zuul
Branch: master

commit 580c8ab5438e18e8224a81362a467f2f37fae86e
Author: Yolanda Robla <email address hidden>
Date: Mon Oct 2 15:44:44 2017 +0200

    Ensure that network.device type exists before using it

    When passing an empty external network definition for the
    undercloud, it was failing because it was assuming to have values
    and a device type. Check if that exists before using it

    Change-Id: I6b573485d373219d257b8c34a252d8490a4c09a0
    Fixes-Bug: #1720796