github/workflows: Add a white space checker
github/workflows: Add a white space checker

Add a GitHub workflow to check for white space issues in pull-requests.

This comes from the git[0] project.

[0]: https://git.kernel.org/pub/scm/git/git.git/tree/.github/workflows/check
-whitespace.yml

Signed-off-by: Andrew Clayton <02e0a999c50b1f88df7a8f5a04e1b76b35ea6a88@digital-domain.net>

ac000/libac