Fix '[combine' when EVDF_TEXTURE_NPOT is disabled. (minetest#12187)

Stop scaling images to POT immediately when loaded. The 'combine'
modifier hardcodes X and Y coordinates, and so behaves incorrectly
if applied to a scaled image. Images emitted by generateImage()
are already scaled to POT before being used as a texture, so
nothing should break.

src/client/tile.cpp

@@ -1109,9 +1109,6 @@ bool TextureSource::generateImagePart(std::string part_of_name,
  // Stuff starting with [ are special commands
  if (part_of_name.empty() || part_of_name[0] != '[') {
  video::IImage *image = m_sourcecache.getOrLoad(part_of_name);
-#if ENABLE_GLES
- image = Align2Npot2(image, driver);
-#endif
  if (image == NULL) {
  if (!part_of_name.empty()) {