On a system with a bwn(4)-supported WiFi chipset:
- kldload if_bwn_pci
- verify that it *does not* attach to the device
- set hw.bwn_pci.preferred tunable.
- kldload if_bwn_pci
- verify that it *does* attach to the device.
On a system with a newer chipset supported only by the new
bhnd(4)-based driver (e.g. BCM4331):
- kldload if_bwn_pci
- verify that it *does* attach to the device.