[PATCH -mm] slqb: use correct name for rcu callback

[Lai Jiangshan <laijs@cn.fujitsu.com>]

struct slqb_page defines struct rcu_head rcu_head for rcu,
the rcu callback should use it.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
---
diff --git a/mm/slqb.c b/mm/slqb.c
index 07bf5b3..48bdf3b 100644
--- a/mm/slqb.c
+++ b/mm/slqb.c
@@ -1026,7 +1043,7 @@ static void rcu_free_slab(struct rcu_head *h)
 {
 	struct slqb_page *page;
 
-	page = container_of((struct list_head *)h, struct slqb_page, lru);
+	page = container_of(h, struct slqb_page, rcu_head);
 	__free_slab(page->list->cache, page);
 }