LU-11915 tests: add debugging to conf-sanity test_115

LU-11915 tests: add debugging to conf-sanity test_115

After updating the e2fsprogs build version to 1.45.2.wc2, this
test is not longer being skipped, and is failing to mount the
newly-formatted OST0000 due to errors registering with the MGS
(target index already in use).  Since the MDS+MGS was just
reformatted, that doesn't make sense.

Continue to skip this test until we understand why it is failing,
but use ALWAYS_EXCEPT instead of blaming the e2fsprogs version.

Test-Parameters: trivial testlist=conf-sanity
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Change-Id: I59c689763481c4fc3677ca1807101de09599bb77
Reviewed-on: https://review.whamcloud.com/37548
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: James Nunez <jnunez@whamcloud.com>
Reviewed-by: Wei Liu <sarah@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>