On O2, the bootpath may omit the pci(0) component and start with scsi(); in that case, fake the pci(0) part in order to match correctly the onboard scsi controller.
On O2, the bootpath may omit the pci(0) component and start with scsi(); in
that case, fake the pci(0) part in order to match correctly the onboard scsi
controller.

While there, make sure device_register() returns early for devices attached
to root; without both these changes, an O2 lacking pci(0) in its bootpath
would dereference a NULL pointer when softraid would attach.

Problem found the hard way by Jukka Taimisto (jtaimisto, iki dot fi), thanks
for the report!

orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars