[clang] [llvm] [Clang][Darwin] Introduce `SubFrameworks` as a SDK default location (PR #115048)

[Cyndy Ishida via cfe-commits]

cyndyishida wrote:

```
> git checkout -f baecb5c50287efebf2482739bfbe320c8147b7ff
error: unable to unlink old 'clang/lib/AST/Decl.cpp': Invalid argument
error: unable to unlink old 'clang/lib/Serialization/ASTReaderDecl.cpp': Invalid argument
```
Seems like an unrelated issue is happening on the windows bot, noticed the same in a different PR. https://buildkite.com/llvm-project/github-pull-requests/builds/116688#0192fe1c-1484-47e8-b14c-7f3da7038b76 

https://github.com/llvm/llvm-project/pull/115048