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

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

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

Test-Parameters: trivial
Signed-off-by: Arshad Hussain <arshad.super@gmail.com>
Change-Id: Idbc8d5cd00b57da8f91b4ce39c40942a7fea8fc3
Reviewed-on: https://review.whamcloud.com/36440
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Shaun Tancheff <stancheff@cray.com>
Reviewed-by: Petros Koutoupis <pkoutoupis@cray.com>