Preliminary EFI support. Based, in part, on patches from Andy Turner. Add support for being able to boot off both UEFI and BIOS firmware, ala the memstick trick. Add support for writing to GPT volumes. Move away from using bsd labels at all for these embedded stuff. Minor tweaks to README.
head/tools/tools/nanobsd/embedded/README
head/tools/tools/nanobsd/embedded/common