LU-5855 tests: enable skipped sanity-lfsck DNE ZFS tests

LU-5855 tests: enable skipped sanity-lfsck DNE ZFS tests

LFSCK has been enabled for DNE striped directories on ZFS for
some time, but the skipped tests have never been enabled for
this configuration.  Re-enable them for ZFS backends.

Fixes: 26995a3588e7 ("LU-5855 lfsck: misc fixes for zfs-based backend")
Test-Parameters: trivial fstype=zfs testlist=sanity-lfsck
Test-Parameters: fstype=zfs mdscount=2 mdtcount=4 testlist=sanity-lfsck
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Change-Id: I33be173c98faa61311ab2b435555cf49e1e2bacc
Reviewed-on: https://review.whamcloud.com/40761
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Lai Siyao <lai.siyao@whamcloud.com>
Reviewed-by: James Nunez <jnunez@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>