[clang] [CIR] Create CIR_TypedAttr common class (PR #136852)

[Henrich Lauko via cfe-commits]

xlauko wrote:

### Merge activity

* **Apr 23, 5:00 PM EDT**: A user started a stack merge that includes this pull request via [Graphite](https://app.graphite.dev/github/pr/llvm/llvm-project/136852).


https://github.com/llvm/llvm-project/pull/136852