The ansible variables containing the list of deployment names that apply
to each server are now written as individual host_vars instead of
group_vars. This change handles the case where a deployment only applies
to a single server (or subset of servers) within a role instead of
applying to all servers in that role.
Change-Id: I06e8de7a81d06445768b729bf9a8e8b58455415f
Closes-Bug: #1798895