Add EXPORT_SYMBOL(ksize);

mm/slub.c exports ksize(), but mm/slob.c and mm/slab.c don't.

It's used by binfmt_flat, which can be built as a module.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>