- remove non-PCI support, since all supported platforms with at_wini
devices also have PCI support by now;
- correspondingly, stop using information from the BIOS altogether;
- limit each driver instance to one controller, to be in line with
the general MINIX3 one-instance-per-controller driver model; this
limits the number of disks per at_wini instance to four;
- go through the controllers by the order of their occurrence in the
PCI table, thus removing the exception for compatibility devices;
- let the second at_wini instance shut down silently if there is only
one IDE controller;
- clean up some extra code we don't need anymore, and resolve some
WARNS=5 level warnings.
Overall, these changes should simplify automatic loading of the right
disk drivers at boot time in the future.
Change-Id: Ia64d08cfbeb9916abd68c9c2941baeb87d02a806
6d466f941b