[llvm] [AArch64] Add AArch64PassRegistry.def (PR #85215)

[via llvm-commits]

paperchalice wrote:

> Can the tests re-use the same CHECK lines, and if not why are they different? Thanks

Only `; RUN: opt -aarch64-lit -mtriple aarch64-unknown-linux-gnu -S < %s | FileCheck %s --check-prefix=NO-TRANSFORM` is different, there is a loop canonicalization stage before running loop passes, it may modify CFG.
https://github.com/llvm/llvm-project/blob/c0d03d28c58f3016eb25ce8d1160e11183d01735/llvm/include/llvm/Transforms/Scalar/LoopPassManager.h#L438-L448

https://github.com/llvm/llvm-project/pull/85215