[llvm] [CodeGen] Port AtomicExpand to new Pass Manager (PR #71220)

[Matt Arsenault via llvm-commits]

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@@ -380,7 +380,7 @@ void NVPTXPassConfig::addIRPasses() {
     addStraightLineScalarOptimizationPasses();
   }
 
-  addPass(createAtomicExpandPass());
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arsenm wrote:

we probably should just put this in the standard pass pipeline instead of forcing every target to add this

https://github.com/llvm/llvm-project/pull/71220