If we can't even get the current device mapper driver version, then we cleanly fail the devmapper driver as not supported and fall back on the next one. Docker-DCO-1.1-Signed-off-by: Alexander Larsson <alexl@redhat.com> (github: alexlarsson) Upstream-commit: 948e54ac455f88c79524dcf117df80f2d4c3f96c Component: engine