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/cs5520.c b/drivers/ide/pci/cs5520.c
index ee10e48..bccedf9 100644
--- a/drivers/ide/pci/cs5520.c
+++ b/drivers/ide/pci/cs5520.c
@@ -197,6 +197,7 @@
 		.autodma	= AUTODMA,			\
 		.bootable	= ON_BOARD,			\
 		.host_flags	= IDE_HFLAG_ISA_PORTS,		\
+		.pio_mask	= ATA_PIO4,			\
 	}
 
 static ide_pci_device_t cyrix_chipsets[] __devinitdata = {