ide: IORDY handling fixes

Add ide_pio_need_iordy() helper and convert host drivers to use it.

This fixes it8172, it8213, pdc202xx_old, piix, slc90e66 and siimage
host drivers to handle IORDY correctly.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/ide/it8172.c

@@ -66,7 +66,7 @@ static void it8172_set_pio_mode(ide_drive_t *drive, const u8 pio)
 	if (drive->media == ide_disk)
 		/* enable prefetch */
 		drive_enables |= 0x0004 << (drive->dn * 4);
-	if (ata_id_has_iordy(drive->id))
+	if (ide_pio_need_iordy(drive, pio))
 		/* enable IORDY sample-point */
 		drive_enables |= 0x0002 << (drive->dn * 4);