Fix VisualTests using glut library for Debug builds.
Fix VisualTests using glut library for Debug builds.

The VisualTests rely on the release version of glut, but our
FindGlutFromOsg gives us the debug library of glut when building
Debug.  Since we never use the debug library, this commit ensures
that we always link to the release library.

simquest/opensurgsim,simquest/opensurgsim,simquest/opensurgsim,simquest/opensurgsim