Add path fallback in tar

Add path fallback in tar

Since current tar defaults to tape devices that are rare nowadays add an
additional step to fallback to "-" if tape devices are not found.

This is a clean way to have a default to "-" on those systems that tape
devices are not present while keeping the current behavior for other
cases. Additionally prepare for future releases where this kind of defaults
will be dropped.

Signed-off-by: Walter Lozano <walter.lozano@collabora.com>