LU-8732 tests: lnet-selftest Error inserting modules

LU-8732 tests: lnet-selftest Error inserting modules

Prevent locally derived module option MODOPTS_LIBCFS being
passed as part of environment variable to remote nodes.
This issue is more prominent in interop setups that have
different version LIBCFS library supporting different module
parameters.

Test-Parameters: trivial testlist=lnet-selftest
Signed-off-by: Abrarahmed Momin <abrar.habib@seagate.com>
Signed-off-by: Arshad Hussain <arshad.hussain@seagate.com>
Change-Id: Ie56103c55611bb62a7dfb314526c48781ab20bc4
Seagate-bug-id: MRP-2675
Reviewed-by: Ujjwal Lanjewar <ujjwal.lanjewar@seagate.com>
Reviewed-by: Ashish Purkar <ashish.purkar@seagate.com>
Reviewed-by: Elena V. Gryaznova <elena.gryaznova@seagate.com>
Tested-by: Elena V. Gryaznova <elena.gryaznova@seagate.com>
Reviewed-on: https://review.whamcloud.com/23250
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Doug Oucharek <doug.s.oucharek@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>