staging/lustre/llite: Update llite_lib.c with proper __user attributes

Casts for get/put_user and copy_to/from_user should have __user
attribute for the userspace buffer address.

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>