Use ANSIBLE_CONFIG for tox -eansible-functional
Use ANSIBLE_CONFIG for tox -eansible-functional

Change-Id: I21e3f5f5adfef4642817049e5dd6c997384e3226
Signed-off-by: Paul Belanger <e7139c8e6c4ea75cc1c287ce081b2dc0f3ab39ec@redhat.com>

openstack/ansible-role-nodepool,openstack/ansible-role-nodepool