Use /usr/share/empty.ssh instead of /var/empty/sshd
This has the following advantages:
* Removes a dependency on a directory stored in /var
* /usr is mounted read only on ostree based systems (CoreOS, Silverblue)
This also removes the tmpfiles config.
Edit Jakub Jelen: Removed the version bump from PR
https://src.fedoraproject.org/rpms/openssh/pull-request/14