[llvm] [llvm][NVPTX] Fix quadratic runtime in ProxyRegErasure (PR #105730)

[Kunwar Grover via llvm-commits]

Groverkss wrote:

Hi! This pr seems to break nvptx compilation. I was able to get a reduced test case:

```
llc test.ll
```

test.ll: https://gist.github.com/Groverkss/d6205367d8bdaff9b848fc14cc9a43a7

https://github.com/llvm/llvm-project/pull/105730