[llvm] Promote the Pseudo Opcode of instructions that deduce the sign extension for extsw from 32 bits to 64 bits when eliminating the extsw instruction in PPCMIPeepholes optimization. (PR #85451)

[Amy Kwan via llvm-commits]

https://github.com/amy-kwan edited https://github.com/llvm/llvm-project/pull/85451