slub statistics: Fix check for DEACTIVATE_REMOTE_FREES

The remote frees are in the freelist of the page and not in the
percpu freelist.
Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Christoph Lameter <clameter@sgi.com>

mm/slub.c

@@ -1368,7 +1368,7 @@ static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
 	struct page *page = c->page;
 	int tail = 1;
 
-	if (c->freelist)
+	if (page->freelist)
 		stat(c, DEACTIVATE_REMOTE_FREES);
 	/*
 	 * Merge cpu freelist into slab freelist. Typically we get here