Hello.

    The fallback to PIO mode in the hwif->dma_check() handler didn't work in
the Intel PIIX and SMsC SLC90E66 IDE drivers because:

  - config_drive_for_dma() called the hwif->speedproc() handler with the wrong
    mode number (unbiased by XFER_PIO_0) in case of the PIO fallback;

  - hwif->tuneproc() handler doesn't really set the drive's own speed (this
    is not fixed as yet).

MBR, Sergei

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>