[llvm] [BOLT] Optimize the codegen of createLoadImmediate for AArch64. (PR #137413)

[Paschalis Mpeis via llvm-commits]

https://github.com/paschalis-mpeis commented:

Hey Rodrigo,

Thanks so much for your work on improving the AArch64 backend.
I'm currently running into some linking errors when trying out the patch:

```
ld.lld: error: undefined symbol: llvm::AArch64_IMM::expandMOVImm(unsigned long, unsigned int, llvm::SmallVectorImpl<llvm::AArch64_IMM::ImmInsnModel>&)
```

https://github.com/llvm/llvm-project/pull/137413