staging: lustre: libcfs: fix sparse warnings about static declaration

Fixes the following sparse warnings:

drivers/staging/lustre/lustre/libcfs/linux/linux-prim.c:198:1: warning:
 symbol 'libcfs_arch_init' was not declared. Should it be static?
drivers/staging/lustre/lustre/libcfs/linux/linux-prim.c:204:1: warning:
 symbol 'libcfs_arch_cleanup' was not declared. Should it be static?

Signed-off-by: Serguey Parkhomovsky <sergueyparkhomovsky@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>