Staging: lustre: lustre: ptlrpc: Add space

ERROR: "(foo*)" should be "(foo *)".That's why add space together.
That Error found with checkpatch.pl

Signed-off-by: Hatice ERTURK <haticeerturk27@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>