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

[Matt Arsenault via cfe-commits]

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@@ -429,6 +429,7 @@ FUNCTION_PASS("strip-gc-relocates", StripGCRelocates())
 FUNCTION_PASS("structurizecfg", StructurizeCFGPass())
 FUNCTION_PASS("tailcallelim", TailCallElimPass())
 FUNCTION_PASS("typepromotion", TypePromotionPass(TM))
+FUNCTION_PASS("atomicexpand", AtomicExpandPass(TM))
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arsenm wrote:

Renaming the pass shouldn't be done in the same change as the new PM support 

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