consoles for TC alphas. Based on code from Takuya Koumoto
<takuya-k@is.aist-nara.ac.jp> as well as some parts of Toru Nishimura's
and Matthias Drochner's work on pmax wscons. This relies on the
NEW_SCC_DRIVER.
is set in the RPB's rpb_variation field. This fixes a bug where machines
(e.g. the 3000/900) would see that they could touch memory where a built-in
PMAGB-BA, assume that it was there, and panic later because the memory they
were accessing didn't look like PMAGB-BA registers (because it wasn't).
briggs