Staging: lustre: Fix initialisation of statics to NULL or 0

This patch fixes the following checkpatch.pl error in
lnet/lnet/config.c:
ERROR: do not initialise statics to 0 or NULL

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>