[llvm] [mlir] [MLIR][NVVM][NVPTX] Support intrinsics about stmatrix (PR #148377)

[Pradeep Kumar via llvm-commits]

schwarzschild-radius wrote:

@Pecco-314 Can you please split the PR into two separate ones? One with NVPTX and one with MLIR changes. Both requires two different reviews and approvals from two different code owners

https://github.com/llvm/llvm-project/pull/148377