staging: lustre: remove unnecessary braces

This patch fixes checkpatch warnings: "WARNING: braces {} are not
necessary for single statement blocks" and "WARNING: braces {} are not
necessary for any arm of this statement".

Signed-off-by: Thibaut Robert <thibaut.robert@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>