This update does three things:

1.  It corrects the compile time warnings/errors on 64 bit platforms
2.  It reverts back to PIO on Intel and Alpha platforms.  It is set up
    to use MMAPed I/O on Power PC platforms, but that's untested and
    may not work (may not even compile).  I'm interested in getting
    this going, so if anyone on a Power PC based system wants to get
    with me, I'll get a working version for the Power PC put together.
3.  As a consequence of going back to PIO on Intel platforms, it's hoped
    that proper instruction ordering in the CPU will help the REQINIT
    handler work properly in more cases.  It already acts correctly in
    *most* cases, but there are still a few isolated reports of the driver
    hanging at bus scan time if certain devices have Wide and/or
    Synchronous negotiation enabled.