ide: add PIO masks

* Add ATA_PIO[0-6] defines to <linux/ata.h>.

* Add ->pio_mask field to ide_pci_device_t and ide_hwif_t.

* Add PIO masks to host drivers.

<linux/ata.h> change ACK-ed by Jeff Garzik <jeff@garzik.org>.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/pci/opti621.c b/drivers/ide/pci/opti621.c
index 1802ad0..3a2bb27 100644
--- a/drivers/ide/pci/opti621.c
+++ b/drivers/ide/pci/opti621.c
@@ -353,12 +353,14 @@
 		.autodma	= AUTODMA,
 		.enablebits	= {{0x45,0x80,0x00}, {0x40,0x08,0x00}},
 		.bootable	= ON_BOARD,
+		.pio_mask	= ATA_PIO3,
 	},{	/* 1 */
 		.name		= "OPTI621X",
 		.init_hwif	= init_hwif_opti621,
 		.autodma	= AUTODMA,
 		.enablebits	= {{0x45,0x80,0x00}, {0x40,0x08,0x00}},
 		.bootable	= ON_BOARD,
+		.pio_mask	= ATA_PIO3,
 	}
 };