Add back support for deprecated export states until tremplin updates

Older versions of lxd/tremplin were doing tar/compress as separate
stages when backing up a container.  Newer versions now do that in a
single pack stage.

This CL adds back support for tar/compress until termina updates
so that these are not considered errors.

Bug: 912638
Change-Id: I42b00f79c03bb5ffc0bba16bc53568ce6c271c5d
Reviewed-on: https://chromium-review.googlesource.com/c/1475685
Commit-Queue: Joel Hockey <joelhockey@chromium.org>
Reviewed-by: Timothy Loh <timloh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#633199}
1 file changed