[llvm] [Analysis][EphemeralValuesAnalysis][NFCI] Remove EphemeralValuesCache class (PR #132454)

[via llvm-commits]

vporpo wrote:

I commented out the new call to `invalidate()` and I am now getting 0.00% change compared to the previous version:
```
     0.40%     -0.00%  clang-21                 [.] llvm::AnalysisManager<llvm::Function>::invalidate(llvm::Function&, llvm::PreservedAnalyses const&)
```
So the 0.05% diff seems to be real.

https://github.com/llvm/llvm-project/pull/132454