message: updated clang-format instructions.
diff: @@ -200,7 +200,8 @@ to determine if the requested feature aligns with the TFLM roadmap.
  tree with
  ```
  - clang-format -i -style=google `git ls-files -m`
  + clang-format -i -style=google `git ls-files -m | grep "\.cc"`
  + clang-format -i -style=google `git ls-files -m | grep "\.h"`
  ```
  1. Make sure your code is lint-free.
  