LU-6142 tests: Fix style issues for mdsrate.c

LU-6142 tests: Fix style issues for mdsrate.c

This patch fixes issues reported by checkpatch
for file lustre/tests/mpi/mdsrate.c

Test-Parameters: trivial
Signed-off-by: Arshad Hussain <arshad.super@gmail.com>
Change-Id: Ibfbadca6af5c915193363a772bc8f6c9a7107ffd
Reviewed-on: https://review.whamcloud.com/35434
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>