[llvm] [NFC][AsmPrinter] Refactor AsmPrinter and AArch64AsmPrinter to prepare for jump table partitions on aarch64 (PR #125993)

[Mingming Liu via llvm-commits]

mingmingl-llvm wrote:

I'll merge as all presubmit tests pass except `Windows Premerge Checks (Test Only - Please Ignore Results)`, which passed its `Build and Test` step (which I interpret as test passes) and failed at `Upload Artifacts`.

https://github.com/llvm/llvm-project/pull/125993