staging/lustre: clean up and remove libcfs/linux/linux-mem.c

Those are simple wrappers for numa allocator. We don't need them.

Signed-off-by: Peng Tao <tao.peng@emc.com>
Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>