In a non-systemd environment the post and preun scripts of libvirt-client
fail, since the required files are in libvirt-daemon. Moved them to client.
Doing that I noticed %{_unitdir}/libvirt-guests.service was contained in
both libvirt-client and libvirt-daemon, which I don't think was intended.
Removed the extra copy from daemon.
Signed-off-by: NViktor Mihajlovski <mihajlov@linux.vnet.ibm.com>