rcutorture: Use ARRAY_SIZE macro when appropriate

Use ARRAY_SIZE macro already defined in kernel.h

Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index 75ca2a7..7d20d76 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -899,7 +899,7 @@
 	/* Set up the freelist. */
 
 	INIT_LIST_HEAD(&rcu_torture_freelist);
-	for (i = 0; i < sizeof(rcu_tortures) / sizeof(rcu_tortures[0]); i++) {
+	for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) {
 		rcu_tortures[i].rtort_mbtest = 0;
 		list_add_tail(&rcu_tortures[i].rtort_free,
 			      &rcu_torture_freelist);