packaging: setup: avoid host name collisions

Doesn't save OVEHOSTED_ENGINE/appHostName in answer file
anymore, avoiding to use that again on additional host.
Propose as default hosted_engine_<host id> instead of
local_host, ensuring different defaults on additional
hosts.

Change-Id: Ide57aa8d88729296b9911a196bbf16357abbe70c
Reported-By: Oved Ourfalli <ovedo@redhat.com>
Signed-off-by: Sandro Bonazzola <sbonazzo@redhat.com>