[libata] sata_sis: use correct S/G table size

sata_sis has the same restrictions as other SFF controllers, and so must
use LIBATA_MAX_PRD to denote that SCSI may only fill ATA_MAX_PRD/2
entries, due to our need to handle IOMMU merging.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/ata/sata_sis.c

@@ -92,7 +92,7 @@ static struct scsi_host_template sis_sht = {
 	.queuecommand		= ata_scsi_queuecmd,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
-	.sg_tablesize		= ATA_MAX_PRD,
+	.sg_tablesize		= LIBATA_MAX_PRD,
 	.cmd_per_lun		= ATA_SHT_CMD_PER_LUN,
 	.emulated		= ATA_SHT_EMULATED,
 	.use_clustering		= ATA_SHT_USE_CLUSTERING,