[libata] Use ATA_UDMAx standard masks when filling driver's udma_mask info

The ATA_UDMAx masks are self-documenting, and far better than manually
writing in the hex mask.

Note that pata_it8213 mask differed from the comment.  Added a FIXME there.

Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/pata_netcell.c b/drivers/ata/pata_netcell.c
index b7c8b13..40eb574 100644
--- a/drivers/ata/pata_netcell.c
+++ b/drivers/ata/pata_netcell.c
@@ -99,7 +99,7 @@
 		   firmware deals with it */
 		.pio_mask	= 0x1f,	/* pio0-4 */
 		.mwdma_mask	= 0x07, /* mwdma0-2 */
-		.udma_mask 	= 0x3f, /* UDMA 133 */
+		.udma_mask 	= ATA_UDMA5, /* UDMA 133 */
 		.port_ops	= &netcell_ops,
 	};
 	const struct ata_port_info *port_info[] = { &info, NULL };