[llvm] [CMAKE][llvm-libraries] Add Precompiled Headers option to improve build times (PR #91755)

[Ameer J via llvm-commits]

ameerj wrote:

> I've tried your patch locally and hitting the error

I believe the issue may have been case sensitivity with some paths, should be resolved with the latest commit.

https://github.com/llvm/llvm-project/pull/91755