message: gltfpack: Fix build warning
  ... which is also a bug that resulted in incorrect image headers when
  using basisu.
diff: @@ -842,7 +842,7 @@ void writeImage(std::string& json, std::vector<BufferView>& views, const cgltf_i
  if (encodeImage(img_data, mime_type.c_str(), encoded, info, settings))
  {
  if (!settings.texture_toktx)
  - encoded = basisToKtx(encoded, info.srgb, settings.texture_uastc);
  + encoded = basisToKtx(encoded, info.srgb, settings.texture_uastc[info.kind]);
  writeEmbeddedImage(json, views, encoded.c_str(), encoded.size(), "image/ktx2", info.kind);
  }
  @@ -871,7 +871,7 @@ void writeImage(std::string& json, std::vector<BufferView>& views, const cgltf_i
  if (encodeImage(img_data, mime_type.c_str(), encoded, info, settings))
  {
  if (!settings.texture_toktx)
  - encoded = basisToKtx(encoded, info.srgb, settings.texture_uastc);
  + encoded = basisToKtx(encoded, info.srgb, settings.texture_uastc[info.kind]);
  if (writeFile(basis_full_path.c_str(), encoded))
  {
  