PCI-ISA bridge. Thus, when viapm0 or viapropm0 attaches, isab0 dosen't
attach so there is no isa0 bus hung off of that bridge. In the non-ACPI
case, legacy0 will add an isa0 anyway as a fail-safe, but ACPI assumes that
any ISA bus will be enumerated via a bridge. To fix this, call
isab_attach() to attach an isa0 ISA child bus device if the pm or propm
device we are probing is a PCI-ISA bridge. Both drivers now have to
implement the bus_if interface via the generic methods for resource
allocation, etc. to work. Also, we now add 2 new ISA bus drivers that
attach to viapm and viapropm devices.
PR: kern/87363
Reported by: Oliver Fromme olli at secnetix dot de
Tested by: glebius
MFC after: 1 week
6647585e2d