The 'luks' driver in qemu is as any other non-raw format driver and thus
doesn't support the properties for 'slice'. Since libvirt considers
luks files to be raw+encryption we need to special case them when
dealing with the slice.

https://bugzilla.redhat.com/show_bug.cgi?id=1814975Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>