Eliminate remaining gcc warnings

Eliminate remaining gcc warnings

Various one-liners (mostly removing unused variables) to make the code
safe for the full set of warnings used by the xorg macros.

On Debian-based systems, flex generates incorrect code resulting in two
warnings about yy_getcolumn and yy_setcolumn having no previous
declaration despite being non-static.  Fedora carries a patch to fix
this, and a bug has been filed on Debian's flex to add the patch:
http://bugs.debian.org/667027

Aside from this, it's now safe for --enable-strict-compilation.

Signed-off-by: Daniel Stone <daniel@fooishbar.org>