- Use device_printf() and device_get_unit() instead of storing the unit
number in the softc.
- Remove use of explicit bus space handles and tags.
- Compare pointers against NULL.
- Let new-bus allocate a softc rather than doing it by hand.
Tested by: no one
now takes a device_t to be the parent of the bus that is being created.
Most SIMs have been updated with a reasonable argument, but a few exceptions
just pass NULL for now. This argument isn't used yet and the newbus
integration likely won't be ready until after 7.0-RELEASE.
