BugLink: http://bugs.launchpad.net/bugs/1594871

Sync with the latest Xenial zfs-linux 0.6.5.6-0ubuntu10
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>