[clang] [llvm] [mlir] [NVPTX] Unify and extend barrier{.cta} intrinsic support (PR #140615)

[Martijn Courteaux via llvm-commits]

mcourteaux wrote:

This merge broke our builds on Halide. 

```
Unhandled exception: Error: Could not find PTX barrier intrinsic (llvm.nvvm.barrier0)
```

We have [an `.ll` file](https://github.com/halide/Halide/blob/main/src/runtime/ptx_dev.ll) declaring these intrinsics:

```ll
declare void @llvm.nvvm.barrier0()
```

So, it seems the auto-upgrade mechanism doesn't work. Any ideas?

https://github.com/llvm/llvm-project/pull/140615