[llvm] [X86] Fix missing check of rotate <-> shift equivilence (Issue 108722) (PR #108767)

[via llvm-commits]

llvmbot wrote:

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>~/cherry-pick 81279bf97f187eee0446af00d8ae9ec32a22e878 1c378d2b145578948942512f9d6985e37659d013~ Going to do this in the issue itself actually.

Error: Command failed due to missing milestone.

https://github.com/llvm/llvm-project/pull/108767