converter fix tar parameter quoting
converter fix tar parameter quoting

The additional quotes in the exclude parameter were not making it to
the tar command which then required tar to extract and create dev
entries.  Fix this by checking shlex.split() output and applying
the changes to the tar command list.

Signed-off-by: Ryan Harper <7c8ea25f69f5166c51151e84bf5db678c2384828@canonical.com>

tpouyer/nova-lxd,Saviq/nova-compute-lxd,Saviq/nova-compute-lxd,mmasaki/nova-compute-lxd,tpouyer/nova-lxd,mmasaki/nova-compute-lxd