Use lxc-3 syntax for tests
Use lxc-3 syntax for tests

Instead of using the Ansible distribution to find out whether lxc-3 is
installed, use the `lxc_three_syntax` variable.

Change-Id: I30f13043d614d6460ef492cfd3d869841fe3ba44
Signed-off-by: Nicolas Bock <4ad6fd604400c7892c7a2cb53bf674987bcaa405@suse.com>

openstack/openstack-ansible-lxc_container_create,openstack/openstack-ansible-lxc_container_create