the bus is configured, interrupts are handled, etc. define
eisa_chipset_tag_t and eisa_intr_handle_t types, and the following
functions:
eisa_attach_hook()
eisa_maxslots()
eisa_intr_map()
eisa_intr_string()
eisa_intr_establish()
eisa_intr_disestablish()
to do the right things for the i386.