[PATCH] usbnet, preliminary zaurus support

This is Pavel's patch, with some cleanups and re-sorting of
the various SA-1100 cases.  According to Pavel this works
as well as his earlier version ... which is to say, maybe
not yet, he saw a uhci "very bad" error (on 2.5.43).

I'm sending it along since it's clearly the right way to
support the Zaurus, and it can't be that far off given the
code I've seen.