We always import privsep modules like this:
import nova.privsep.libvirt
Not like this:
from nova.privsep import libvirt
This is because it makes it obvious at the caller that a priviledged
operation is occuring:
nova.privsep.libvirt.destroy_root_filesystem()
Not just:
libvirt.destroy_root_filesystem()
This is especially true when the imported module is called "libvirt",
which is a very common term in the codebase and super hard to grep
for specific uses of.
I've corrected the existing style mismatches to make things consistent.
Note that the next patch in this series covers this case with a
hacking check.
Change-Id: Ief177dbcb018da6fbad13bb0ff153fc47292d5b9
3aa702686b