LU-6142 obd: Fix style issues for obd.h

LU-6142 obd: Fix style issues for obd.h

This patch fixes issues reported by checkpatch
for file lustre/include/obd.h

Test-Parameters: trivial
Signed-off-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>
Change-Id: I98b0f4e3b5849d2c917c6236948770c94a497c41
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/56299
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Chris Horn <chris.horn@hpe.com>
Reviewed-by: Timothy Day <timday@amazon.com>
Reviewed-by: Petros Koutoupis <petros.koutoupis@hpe.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>