[LinuxBIOS] ELF loader in v3

[ron minnich]

The 'copy yourself out of the way' elfboot code was incredibly
powerful and fun to read. It was also tricky.

For the first pass, I yanked it from v3 as I had too many 'what the
hell is this doing' questions over the years. It reduced from 668
tricky lines to 215 dead-simple lines. But we also lost the ability to
run arbitrary code. That ability was almost never needed, however.

It would actually be simpler, if we want arbitrary ability to to copy
code around, to put a final 'copy it around' function in ROM, run all
stages of LinuxBIOS, and run the 'copy it all around' bit in ROM.

Or: We do several uncompress lar to rom, run, return to rom phases
now, The final copy step could be a final lar entry.

There are actually lots of ways to do support arbitrary code
destination,  all of them simpler than what we did in V2. I'd like to
explore alternatives before we put the v2 code back.

thanks

ron