ofw_fdt_finddevice
root = ofw_fdt_finddevice(NULL, "/");
if ((root = ofw_fdt_finddevice(ofw, "/")) == -1)
static phandle_t ofw_fdt_finddevice(ofw_t, const char *);
OFWMETHOD(ofw_finddevice, ofw_fdt_finddevice),