[llvm] [AArch64][MacroFusion] Fuse only tied AES pairs (PR #196484)

[David Green via llvm-commits]

https://github.com/davemgreen commented:

It is still not clear why you are changing this exactly and what it makes better. Especially for pre ra scheduling where the registers will be different, but might be the same later. 

Does AESMCrr get used with FuseAES in a way that this is reachable? 

https://github.com/llvm/llvm-project/pull/196484