at91_ide: turn on PIO 6 support

As we have already PIO 6 transfer mode supported in IDE layer, we can turn
it on in the driver.

Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl>
Tested-by: "Steve Wootton" <swootton@esi-estech.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/ide/at91_ide.c

@@ -215,7 +215,7 @@ static const struct ide_port_info at91_ide_port_info __initdata = {
 	.tp_ops		= &at91_ide_tp_ops,
 	.host_flags 	= IDE_HFLAG_MMIO | IDE_HFLAG_NO_DMA | IDE_HFLAG_SINGLE |
 			  IDE_HFLAG_NO_IO_32BIT | IDE_HFLAG_UNMASK_IRQS,
-	.pio_mask 	= ATA_PIO5,
+	.pio_mask 	= ATA_PIO6,
 };
 
 /*