memcg: remove unnecessary return from void-returning mem_cgroup_del_lru_list()

Signed-off-by: NMinchan Kim <minchan.kim@gmail.com>
Acked-by: NBalbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mm/memcontrol.c

@@ -821,7 +821,6 @@ void mem_cgroup_del_lru_list(struct page *page, enum lru_list lru)
 		return;
 	VM_BUG_ON(list_empty(&pc->lru));
 	list_del_init(&pc->lru);
-	return;
 }
 
 void mem_cgroup_del_lru(struct page *page)