[llvm] [NVPTX] disable combine-mad test for newer ptxas (PR #93919)

[Alex MacLean via llvm-commits]

AlexMaclean wrote:

@Artem-B, this addresses your request from https://github.com/llvm/llvm-project/pull/93628#discussion_r1621453827. Can you clarify what version of ptxas you're using and what error you're seeing?

https://github.com/llvm/llvm-project/pull/93919