SLUB: slabinfo fixes

Align the output of % with K/M/G of sizes.

Check for empty NUMA information to avoid segfault on !NUMA.

-r should work directly not only if we match a single slab
   without additional options.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>