md: convert cpu notifier to return encapsulate errno value

By the previous modification, the cpu notifier can return encapsulate
errno value.  This converts the cpu notifiers for raid5.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/md/raid5.c

@@ -4645,7 +4645,7 @@ static int raid456_cpu_notify(struct notifier_block *nfb, unsigned long action,
 			kfree(percpu->scribble);
 			pr_err("%s: failed memory allocation for cpu%ld\n",
 			       __func__, cpu);
-			return NOTIFY_BAD;
+			return notifier_from_errno(-ENOMEM);
 		}
 		break;
 	case CPU_DEAD: