message: Fix GL2 texparam setting
diff: @@ -177,8 +177,8 @@ void TransferFunction::render(ospray::async_render_engine &renderEngine){
  glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, samples, 1, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0);
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
  - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
  + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
  + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
  if (prev_binding) {
  glBindTexture(GL_TEXTURE_2D, prev_binding);
  