tests/pkg/emlearn: fix wrong model header file name in README

Author: aabadie

tests/pkg/emlearn/README.md

@@ -35,6 +35,6 @@ The application comes with 3 Python scripts:
   $ ./train_model.py
   ```
   will just train the model.
-- `generate_model.py` is used to generate the `sonar.h` header file from the
+- `generate_model.py` is used to generate the `model.h` header file from the
   `model` binary file. The script is called automatically by the build system
   when the `model` binary file is updated.