abort if WINEDEBUG requests functionality that was disabled at configure time

[Tomas Carnecky]

Mike Hearn wrote:
> Why would anybody build without tracing anyway? I would be *very*
> surprised if it led to any noticable/real world performance improvement.

Because of the exact same reason NVidia doesn't want to add yet another
dispatch table to linux's OpenGL libraries (as proposed by someone on
the xorg ML to add support for a new fancy feature), for functions that
are used heavily and are very small (like glBegin()) it decreases the
performance by up to 30% for certain applications (I think it was an
opengl test suite). I know the overhead of an dispatch table is bigger
than a simple 'if (trace) {}', but this few (load, compare == two?)
additional instruction still is noticeable in certain applications.

tom