mm/slab: Sharing s_next and s_stop between slab and slub

This patch shares s_next and s_stop between slab and slub.

Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

mm/slab.h

diff --git a/mm/slab.h b/mm/slab.h
index f96b49e..95c8860 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -271,3 +271,6 @@
 #endif
 
 };
+
+void *s_next(struct seq_file *m, void *p, loff_t *pos);
+void s_stop(struct seq_file *m, void *p);