slub: Fix a typo in config name

There's no config named SLAB_DEBUG, and it should be a typo
of SLUB_DEBUG.

Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
diff --git a/mm/slub.c b/mm/slub.c
index f881874..129f10c 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -3203,7 +3203,7 @@
 			list_for_each_entry(p, &n->partial, lru)
 				p->slab = s;
 
-#ifdef CONFIG_SLAB_DEBUG
+#ifdef CONFIG_SLUB_DEBUG
 			list_for_each_entry(p, &n->full, lru)
 				p->slab = s;
 #endif