LU-9624 tests: fix pre-DNE test exceptions/llog usage

LU-9624 tests: fix pre-DNE test exceptions/llog usage

Remove some test skips when running with multiple MDTs in DNE mode,
or fix tests to work better with multiple MDTs.  Tests updated are:
recovery-small: 60
sanity: 17hi, 154ab, 160abcde, 161abcd, 162a, 205, 225ab, 254, 256

In particular, sanity.sh test_160, test_161, test_162 ignored test
failures in DNE mode.  Fix test_160* to work with ChangeLogs stored
on multiple MDTs.  This adds test coverage both because we aren't
skipping these tests when running in DNE mode, but also because we
are now validating ChangeLogs running on multiple MDTs at once.

Test-Parameters: trivial mdscount=2 mdtcount=4 testlist=sanity,recovery-small,sanity-hsm
Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
Change-Id: I3fc3ce85b46f34e507c1e28b4c76574a698cab07
Reviewed-on: https://review.whamcloud.com/27535
Tested-by: Jenkins
Reviewed-by: James Nunez <james.a.nunez@intel.com>
Reviewed-by: Quentin Bouget <quentin.bouget@cea.fr>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Sebastien Buisson <sbuisson@ddn.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>