LU-3939 tests: sanity-hsm/test_40 needs a local HSM_ARCHIVE

LU-3939 tests: sanity-hsm/test_40 needs a local HSM_ARCHIVE

sanity-hsm/test_40 suffers frequent failures during auto-test due
to remote/NFS-mounted HSM_ARCHIVE causing the 400 archive requests
to take more than 100s to be drained from copytool requests queue.
This patch allows copytool_setup func to allow each sub-test to
specify a non-default hsm-root/HSM_ARCHIVE dir and test_40 uses it.

This patch is back-ported from the following one:
Lustre-commit: 8484f1c51c701141237e98a1467c75364766f357
Lustre-change: http://review.whamcloud.com/7703

Signed-off-by: Bruno Faccini <bruno.faccini@intel.com>
Change-Id: I733b267991faa3b8c9415fea116d2086575333bb
Signed-off-by: Jian Yu <jian.yu@intel.com>
Reviewed-on: http://review.whamcloud.com/8771
Tested-by: Jenkins
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>