memcg: fix broken boolen expression

action != CPU_DEAD || action != CPU_DEAD_FROZEN is always true.
Signed-off-by: NKirill A. Shutemov <kirill@shutemov.name>
Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: NMichal Hocko <mhocko@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mm/memcontrol.c

@@ -2165,7 +2165,7 @@ static int __cpuinit memcg_cpu_hotplug_callback(struct notifier_block *nb,
 	if (action == CPU_ONLINE)
 		return NOTIFY_OK;
 
-	if ((action != CPU_DEAD) || action != CPU_DEAD_FROZEN)
+	if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
 		return NOTIFY_OK;
 
 	for_each_mem_cgroup(iter)