revert. my 'fix' was an error which made sm use software fallback. opengl still slow on ati cards

stepmania/Data/Shaders/GLSL/Texture matrix scaling.vert

@@ -5,7 +5,7 @@ void main(void)
 	gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
 	vec4 multiplied_tex_coord = gl_TextureMatrix[0] * gl_MultiTexCoord0;
 	gl_TexCoord[0] = (multiplied_tex_coord * TextureMatrixScale) +
-			(gl_MultiTexCoord0 * (vec4(1)-TextureMatrixScale);
+			(gl_MultiTexCoord0 * (vec4(1)-TextureMatrixScale));
 	gl_FrontColor = gl_Color;
 }