[llvm] [NVPTX] Skip processing BasicBlocks with single unreachable instruction in `nvptx-lower-unreachable` pass. (PR #72641)

[Artem Belevich via llvm-commits]

Artem-B wrote:

> You can use -mllvm -nvptx-exit-on-unreachable=0

This option appears to be gone now. https://github.com/llvm/llvm-project/pull/67478

https://github.com/llvm/llvm-project/pull/72641