The upgrade fact set was more complex than it
needed to be, and we can use better inventory
scoping combined with ansible_play_hosts in
order to make the execution more friendly to
limited execution.
We also cater for setting facts even if the
new role is being used without the venv
changing.
Depends-On: I90d09fe354d87b099024019ceeb2b7e129ef35d0
Change-Id: I97ace7c89dc7015e2e740516695d4e61971cf020
8f1781a655