add glue for network interfaces to be found by fdt/ofw node or phandle.
if we're going to support switch chips (eg, marvell link street
switches as found on a3700 boards like the espressobin), then the
device tree for switch ports identifies which network interface
they're connected by by a reference (phandle) across the device
tree. this lets network drivers register the ifnet struct with the
associated node and phandle so the switch can find it and configure
it for use with the switch.
ok kettenis@
projects / openbsd / commit