LU-15358 tests: Variable incorrectly defined under sanityn

LU-15358 tests: Variable incorrectly defined under sanityn

Under sanityn.sh/print_jbd_stat() local variable
was incorrectly defined. This was exposed using
shellcheck.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In lustre/tests/sanityn.sh line 950:
local varcvs
      ^-- SC2034: varcvs appears unused. Verify it or export it.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Test-Parameters: trivial testlist=sanityn
Signed-off-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>
Change-Id: I7b2f62c15e420a4c6f5d71445a2e940816e20098
Reviewed-on: https://review.whamcloud.com/45819
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: James Nunez <jnunez@whamcloud.com>