The version will initially remain the same so that no additional changes
to the packaging are required (i.e. this commit only includes the
required changes to build from the mono repository instead of individual
tarballs).
The purpose of this package is to continuously improve the LLVM
packaging in Nixpkgs without causing a lot of rebuilds and provide more
recent LLVM builds for users. For more details see:
https://github.com/NixOS/nixpkgs/issues/114828
