[llvm] [FixIrreducible] Handle conditional branch with both successors as header (PR #206057)

[Robert Imschweiler via llvm-commits]

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@@ -0,0 +1,27 @@
+; NOTE: Do not autogenerate
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ro-i wrote:

why no autogenerated output?

https://github.com/llvm/llvm-project/pull/206057