[clang] [clang][ssaf] Consolidate tools and shared utilities under `clang/tools/clang-ssaf/` (PR #187439)

[Balázs Benics via cfe-commits]

https://github.com/steakhal requested changes to this pull request.

One directory should either declare a target for a single library or a single binary.
This CMakeList.txt violates this rule.

https://github.com/llvm/llvm-project/pull/187439