Ported sfml-pi DRM/KMS backend written by @mickelson
Port co-authored by @substring
Co-authored-by: Andrew Mickelson <andrew.mickelson@gmail.com>
Co-authored-by: Gil Delescluse <frog2wah@gmail.com>
When a single GitHub Action build fails, the other builds should not be
canceled, but instead should continue to build.
Since the matrix is setup on OS level, a failing build on one OS usually
doesn't mean it's broken for all OS.