licensing: make the project REUSE-compliant
In order to make the licensing situation of libgpiod clear and enable
easy reusing of the code, let's make all the files in the repository
compliant with the REUSE v3.0 specification.
In order to achieve that:
- put all used licenses into a separate LICENSES/ directory
- add SPDX license identifiers to all files that were missing them with
regular text files being licensed under CC-BY-SA-4.0, while files
containing code and configuration are licensed under GPL-2.0-or-later
- replace custom copyright texts with SPDX-FileCopyrightText
- update the gpio.h kernel uAPI header with the upstream version where
the SDPX license identifier was fixed to use 'GPL-2.0-only' variant
instead of the deprecated 'GPL-2.0'
Signed-off-by: Bartosz Golaszewski <email@example.com>
Acked-by: Kent Gibson <firstname.lastname@example.org>
87 files changed