siimage: fix ->set_pio_mode method to select PIO data transfer

* Remember to select PIO data transfer (with IORDY monitored) in sil_tune_pio()
  (->set_pio_mode method) so the controller is always programmed correctly for
  PIO transfers (this is important if DMA is not going to be used).

* Don't set DMA/UDMA timings for PIO modes in siimage_tune_chipset().

* Bump driver version.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>