Recent change to devstack [1] broke our DHSS=False CI job running
generic driver that was depending on ip route from host to
private network. So, to avoid this error use floating ip address
for connection to service Nova VMs from host machine.
Also, fix generation of second export location that should be dedicated
for service needs such as mounting share doing host-assisted
migration.
[1] If45e3fc15c050cfbac11b57c1eaf137dd7ed816f
Change-Id: Ieea992293ae02898741c939da15f0dbb4609d8b0
Closes-Bug: #1644523
Closes-Bug: #1646097
8c5ed29ba6