sun4v_walk
root_node = sun4v_walk(&sys_tree, NULL, next(0));
pnode->child = sun4v_walk(tree, pnode, curnode);
return (sun4v_walk(tree, root, curnode));
pnode->sibling = sun4v_walk(tree, root, curnode);
Prom_node *sun4v_walk(Sys_tree *, Prom_node *, int);