[llvm] [AArch64][LoopIdiom] Generalize AArch64LoopIdiomTransform into LoopIdiomTransform (PR #94081)

[Min-Yih Hsu via llvm-commits]

mshockwave wrote:

> Can we please split this into two changes, one which does the move and rename, and a second which adds the new functionality? This diff is slightly confusing as a reader.

I don't think I add any new functionalities in this patch, the support for RVV-style vectorization is in #94082 

> 
> Naming wise, maybe LoopIdiomVectorizer? And update the comment to be really explicit about the goal being to eventually kill this off as the vectorizer grows more powerful?

I second for LoopIdiomVectorizer.

https://github.com/llvm/llvm-project/pull/94081