slub: improve kmem_cache_destroy() error message
slub: improve kmem_cache_destroy() error message

As pointed out by Ingo, the SLUB warning of calling kmem_cache_destroy()
with cache that still has objects triggers in practice. So turn this
WARN_ON() into a nice SLUB specific error message to avoid people
confusing it to a SLUB bug.

Cc: Ingo Molnar <9dbbbf0688fedc85ad4da37637f1a64b8c718ee2@elte.hu>
Acked-by: Christoph Lameter <a2610c5c148280bb6730402b12a8276c2f194fbe@sgi.com>
Signed-off-by: Pekka Enberg <add4fcd06328a394f0ad91feda7ee057316dc5ed@cs.helsinki.fi>

TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs