d0a5ff1050
Sometimes gates fails due lack of space,
post merge jobs gates fails always for oraclelinux
binary, not being able create a tarball registry.
This change mounts a second disk in opt and moves
registry data to opt.
Disk format commands are excepts from devstack-gate:
dc49f9e6eb/functions.sh (L306)
Closes-Bug: #1713652
Change-Id: I883e51042841709eb9ab348cfdce9fecbd4fb890