Staging: lustre: Deleted space prohibited between function name and open parenthesis

WARNING: space prohibited between function name and open parenthesis '('
Remove unnecessary space between function name and opening parenthesis.
That was found by running checkpatch.pl

Signed-off-by: Dilek Uzulmez <dilekuzulmez@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>