slub: mark the dangling ifdef #else of CONFIG_SLUB_DEBUG

The #ifdef of CONFIG_SLUB_DEBUG is located very far from the associated
#else.  For readability mark it with a comment.

Signed-off-by: Jesper Dangaard Brouer <[email protected]>
Acked-by: Christoph Lameter <[email protected]>
Cc: Pekka Enberg <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Alexander Duyck <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

mm/slub.c

@@ -1204,7 +1204,7 @@ unsigned long kmem_cache_flags(unsigned long object_size,
 
 	return flags;
 }
-#else
+#else /* !CONFIG_SLUB_DEBUG */
 static inline void setup_object_debug(struct kmem_cache *s,
 			struct page *page, void *object) {}