ide: add drive->dma_mode field

Add dma_mode field to ide_drive_t matching dma_mode field used in
struct ata_device.

The validity of the field is restricted to ->dma_pio_mode method
only currently in IDE subsystem.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/ide.h b/include/linux/ide.h
index b5d2e96..746ef9f 100644
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -516,6 +516,7 @@
         u8	current_speed;	/* current transfer rate set */
 	u8	desired_speed;	/* desired transfer rate set */
 	u8	pio_mode;	/* for ->set_pio_mode _only_ */
+	u8	dma_mode;	/* for ->dma_pio_mode _only_ */
         u8	dn;		/* now wide spread use */
 	u8	acoustic;	/* acoustic management */
 	u8	media;		/* disk, cdrom, tape, floppy, ... */