LU-12506 mdc: clean up code style for mdc_locks.c

LU-12506 mdc: clean up code style for mdc_locks.c

Clean up code style in mdc_locks.c (whitespace, strings)

Run a useful test while we are at it.

Test-Parameters: trivial testlist=runtests mdscount=10 mdtcount=80
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Change-Id: I3e3e0a6a4712e8bc85c93c0a182afa00433ebbe5
Reviewed-on: https://review.whamcloud.com/37917
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Arshad Hussain <arshad.super@gmail.com>
Reviewed-by: Shaun Tancheff <shaun.tancheff@hpe.com>
Reviewed-by: Hongchao Zhang <hongchao@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>