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

make sparse happy since these two fuchtion are only used in module.c.
tested by successful compilation.

Signed-off-by: Jia He <hejianet@gmail.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: Andreas Dilger <andreas.dilger@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>