LU-5622 tests: check/wait for copytool death

LU-5622 tests: check/wait for copytool death

Seems that copytool death/kill may take more time so
this condition must be handled in sanity-hsm copytool_cleanup()
function to avoid situations where copytool will then not be
restarted, but only signaled, in next copytool_setup().

This patch is back-ported from the following one:
Lustre-commit: 6facf3953b170832200ca9c111398da8feecd281
Lustre-change: http://review.whamcloud.com/11922

Signed-off-by: Bruno Faccini <bruno.faccini@intel.com>
Change-Id: Ia817936eb030386dbe539ec8d5297812f4b6fff2
Reviewed-on: http://review.whamcloud.com/12967
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: James Nunez <james.a.nunez@intel.com>
Reviewed-by: Henri Doreau <henri.doreau@cea.fr>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>