We take the approach to detect zero data when restoring and not
writing it out to the volume. This works exactly as expected
when restoring into Linux LVM volumes and into Ceph RBD volumes,
provided they are freshly created.
Closes-bug: #2007615
Change-Id: I54b81a568a01af44e3f74bcac55e823cdae9bfbf
(cherry picked from commit 477b1342747ddeb3ab9a586b33c06f1e51f37df8)
c56b79caa3