Remove Ubuntu 14.04 related code
Remove Ubuntu 14.04 related code

Last Openstack version supported on Ubuntu 14.04 is Mitaka.
Hence Ubuntu 14.04 related code can be safely remove from Ansible tasks
since Kolla Newton release.

Change-Id: I7202c1f6d21a2e6f3536c0420a7cc889aff0f5ed

dardelean/kolla-ansible,dardelean/kolla-ansible,dardelean/kolla-ansible