LU-6675 tests: Improve error detection replay-single test 80

LU-6675 tests: Improve error detection replay-single test 80

The replay-single tests 80a - 80d call remote_dir_check_80. This
subroutine does not check the return code of 'lfs getstripe' which
results in bash errors in when checking the return of getstrip.

Signed-off-by: James Nunez <james.a.nunez@intel.com>
Change-Id: I6c7e974aff38c13afc38594327d4a11ac5efd60b
Reviewed-on: http://review.whamcloud.com/15111
Tested-by: Jenkins
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Cliff White <cliff.white@intel.com>
Reviewed-by: Justin Miller <jmiller@cray.com>