sata_mv: Clean up hard coded array size calculation.

Use ARRAY_SIZE macro of kernel api instead.
Signed-off-by: NThiago Farina <tfransosi@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

drivers/ata/sata_mv.c

@@ -2217,7 +2217,7 @@ static unsigned int mv_qc_issue_fis(struct ata_queued_cmd *qc)
 	int err = 0;
 
 	ata_tf_to_fis(&qc->tf, link->pmp, 1, (void *)fis);
-	err = mv_send_fis(ap, fis, sizeof(fis) / sizeof(fis[0]));
+	err = mv_send_fis(ap, fis, ARRAY_SIZE(fis));
 	if (err)
 		return err;