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

[Justin Fargnoli via llvm-commits]

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@@ -897,11 +897,6 @@ let Predicates = [hasOptEnabled] in {
   defm MAD_LO_S16 : MADInst<"lo.s16", mul, I16RT, I16RT>;
   defm MAD_LO_S32 : MADInst<"lo.s32", mul, I32RT, I32RT>;
   defm MAD_LO_S64 : MADInst<"lo.s64", mul, I64RT, I64RT>;
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justinfargnoli wrote:

Given that these are now the only uses of `MADInst`, should I eliminate some of the abstraction provided by `MADInst`? 

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