Move gate-neutron-dsvm-tempest-vpnaas-ubuntu-xenial-nv out of
experimental.
Also, retire gate-neutron-vpnaas-dsvm-api-ubuntu-xenial-nv
because it only runs a subset of the new job.
Closes-Bug: #1659691
Depends-On: I81e712503a20623bf43bd61c39f79efc306f8e9a
Change-Id: I5a4511db59a4beb344d94f1ffd8826e1a4a35726
Liberty is EOL, start cleaning up all of the special things we have in
place for handling libertyisms. Note that this doesn't touch the configs
for deployment projects as they may still attempt to support liberty via
distro packages.
Change-Id: I7faa16c1d6038204a4b42167ed91b73175abe58c