Remove some variables which were set but not used.

Remove some variables which were set but not used.

gcc (at least as of version 4.6.0) is kind enough to point these out to us,
(when given -Wunused-but-set-variable explicitly or implicitly via -Wunused
or -Wall).

One of these cases was a legitimately unused variable. Two were simply
variables (named ignored) we were assigning only to squelch a warning about
unused function return values. I don't seem to be getting those warnings
even without setting the ignored variable. And the gcc docs. say that the
correct way to squelch that warning is with a cast to (void) anyway.