[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/ata_piix.c b/drivers/ata/ata_piix.c
index 76cbdf0..6a3bfef 100644
--- a/drivers/ata/ata_piix.c
+++ b/drivers/ata/ata_piix.c
@@ -497,7 +497,7 @@
 		.flags		= PIIX_SATA_FLAGS,
 		.pio_mask	= 0x1f,	/* pio0-4 */
 		.mwdma_mask	= 0x07, /* mwdma0-2 */
-		.udma_mask	= 0x7f,	/* udma0-6 */
+		.udma_mask	= ATA_UDMA6,
 		.port_ops	= &piix_sata_ops,
 	},
 
@@ -507,7 +507,7 @@
 		.flags		= PIIX_SATA_FLAGS | PIIX_FLAG_SCR,
 		.pio_mask	= 0x1f,	/* pio0-4 */
 		.mwdma_mask	= 0x07, /* mwdma0-2 */
-		.udma_mask	= 0x7f,	/* udma0-6 */
+		.udma_mask	= ATA_UDMA6,
 		.port_ops	= &piix_sata_ops,
 	},
 
@@ -518,7 +518,7 @@
 				  PIIX_FLAG_AHCI,
 		.pio_mask	= 0x1f,	/* pio0-4 */
 		.mwdma_mask	= 0x07, /* mwdma0-2 */
-		.udma_mask	= 0x7f,	/* udma0-6 */
+		.udma_mask	= ATA_UDMA6,
 		.port_ops	= &piix_sata_ops,
 	},
 
@@ -529,7 +529,7 @@
 				  PIIX_FLAG_AHCI,
 		.pio_mask	= 0x1f,	/* pio0-4 */
 		.mwdma_mask	= 0x07, /* mwdma0-2 */
-		.udma_mask	= 0x7f,	/* udma0-6 */
+		.udma_mask	= ATA_UDMA6,
 		.port_ops	= &piix_sata_ops,
 	},
 
@@ -540,7 +540,7 @@
 				  PIIX_FLAG_AHCI,
 		.pio_mask	= 0x1f,	/* pio0-4 */
 		.mwdma_mask	= 0x07, /* mwdma0-2 */
-		.udma_mask	= 0x7f,	/* udma0-6 */
+		.udma_mask	= ATA_UDMA6,
 		.port_ops	= &piix_sata_ops,
 	},