allows us to move the sio softc data structure back into sio.c and
reduce the complexity of the non sio.c sio files.
Submitted by: bde
# I didn't fix the locking issues that bruce also submitted.
sio_pccard_detach to use new siodetach. Add an extra arg to sioprobe
to tell driver to probe/not probe the device for IRQs.
This incorporates most of Bruce's review material. I'm at a good
checkpoint, but there will be more to come based on bde's further
reviews.
Reviewed by: bde
