- Garbage collect some cruft that doesn't apply to the ofppc port.
- Make our OFW-friendly alloc.c more like the libsa alloc.c
- Generally reduce some differences where we can between this
boot loader and the NetBSD/macppc boot loader.
- Use libsa's loadfile().
- Fix DDB symbol loading -- Add a magic number after the args string
so the kernel knows the symbols are there, provide both ssym and
esym, and make sure all these values are aligned to a 4-byte boundary.
- Add support for MS-DOS file systems.