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/ide.c b/drivers/ide/ide.c
index b442b34..f3ea5ea 100644
--- a/drivers/ide/ide.c
+++ b/drivers/ide/ide.c
@@ -457,6 +457,8 @@
 
 	hwif->host_flags		= tmp_hwif->host_flags;
 
+	hwif->pio_mask			= tmp_hwif->pio_mask;
+
 	hwif->atapi_dma			= tmp_hwif->atapi_dma;
 	hwif->ultra_mask		= tmp_hwif->ultra_mask;
 	hwif->mwdma_mask		= tmp_hwif->mwdma_mask;