[clang] [NFC] Delete unused clang-formatted-file.txt/ClangFormattedStatus.rst files (PR #109220)

[Chris Apple via cfe-commits]

cjappl wrote:

FYI @jurahul  - having a build failure when I try to build docs after this change. I think a few little bits were missed.
```
Warning, treated as error:
./llvm-project/build/tools/clang/docs/ClangFormattedStatus.rst:document isn't included in any toctree
```

https://github.com/llvm/llvm-project/blob/847f4ef21b4a953bb6dd6477791e8d95b6db2509/clang/docs/ClangFormat.rst?plain=1#L370

https://github.com/llvm/llvm-project/blob/847f4ef21b4a953bb6dd6477791e8d95b6db2509/clang/docs/tools/generate_formatted_state.py#L32

https://github.com/llvm/llvm-project/blob/847f4ef21b4a953bb6dd6477791e8d95b6db2509/clang/docs/tools/generate_formatted_state.py#L59

Would you mind reverting (or just deleting these, if that is more appropriate)?

https://github.com/llvm/llvm-project/pull/109220