in_devwalk
np = in_devwalk(dip, &ap, NULL);
np = in_devwalk(dip, &ap, NULL);
ASSERT(np == in_devwalk(dip, &ap, NULL));
static in_node_t *in_devwalk(dev_info_t *dip, in_node_t **ap, char *addr);
np = in_devwalk(dip, &ap, addr);
np = in_devwalk(dip, &ap, NULL);
np = in_devwalk(ddi_get_parent(dip), ap, NULL);