[clang] [llvm] [mlir] [NVPTX] Add support for Shared Cluster Memory address space. (PR #135444)

[via llvm-commits]

modiking wrote:

> A general thought, Can we include the base changes in this PR and create a separate PR for the intrinsics-migration+MLIR changes?

That makes sense, will do once we're happy with all the changes.

https://github.com/llvm/llvm-project/pull/135444