Add clang-format package for Neon
This is needed for the automated code formatting used in frameworks, plasma and applications. These repos can still be build without clang-format, but then the pre-commit hook will be disabled and the developer is more likely to push unformatted changes.
I have only done this for neon, because I could not test it with other distros.
@ahmadsamir Maybe you could do the same for openSUSE?