[llvm] [NVPTX] Fix ptxas requirements (PR #171219)

[Drew Kersnar via llvm-commits]

dakersnar wrote:

Sorry for making this mistake again. You beat me to the punch but I put up a fix here too: https://github.com/llvm/llvm-project/pull/171220.

I think you solution might be better (it uses the minimum ptx and arch versions where this feature is allowed, unlike mine which uses a later one) but I think you will see a small change in the check output in LoadStoreVectorizer.ll.

https://github.com/llvm/llvm-project/pull/171219