[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/aic7xxx/aic7xxx_proc.c b/drivers/scsi/aic7xxx/aic7xxx_proc.c
index 04a3506..5914b4a 100644
--- a/drivers/scsi/aic7xxx/aic7xxx_proc.c
+++ b/drivers/scsi/aic7xxx/aic7xxx_proc.c
@@ -77,11 +77,9 @@
 ahc_calc_syncsrate(u_int period_factor)
 {
 	int i;
-	int num_syncrates;
 
-	num_syncrates = sizeof(scsi_syncrates) / sizeof(scsi_syncrates[0]);
 	/* See if the period is in the "exception" table */
-	for (i = 0; i < num_syncrates; i++) {
+	for (i = 0; i < ARRAY_SIZE(scsi_syncrates); i++) {
 
 		if (period_factor == scsi_syncrates[i].period_factor) {
 			/* Period in kHz */