[llvm] Partial revert "[NVPTX] Enhance mul.wide and mad.wide peepholes#150477" (PR #155024)

[Justin Fargnoli via llvm-commits]

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justinfargnoli wrote:

The tests in this file were added to verify the generation of `mad.wide`. Now that that behavior has been removed, they're checking that the combine does not happen. Any preferences on whether we remove the tests or keep them? 

https://github.com/llvm/llvm-project/pull/155024