[SCSI] drivers/scsi: Use ARRAY_SIZE macro

Use ARRAY_SIZE macro instead of sizeof(x)/sizeof(x[0]) and remove
duplicates of the macro.

Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index a112e49..3541990 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -175,7 +175,7 @@
 		 * it's not worth the risk */
 		return -EINVAL;
 
-	for (i = 0; i < sizeof(sd_cache_types)/sizeof(sd_cache_types[0]); i++) {
+	for (i = 0; i < ARRAY_SIZE(sd_cache_types); i++) {
 		const int len = strlen(sd_cache_types[i]);
 		if (strncmp(sd_cache_types[i], buf, len) == 0 &&
 		    buf[len] == '\n') {