bus_generic_attach_gpri
bus_generic_attach_gpri(bus, KOBJ_GPRI_ACPI+2);
bus_generic_attach_gpri(bus, KOBJ_GPRI_ACPI+1);
bus_generic_attach_gpri(bus, KOBJ_GPRI_ACPI);
bus_generic_attach_gpri(bus, KOBJ_GPRI_ACPI);
int bus_generic_attach_gpri(device_t dev, u_int gpri);