[clang] [llvm] [aarch64][clang][llvm] Allow AArch64 TLB maintenance instructions to be enabled via -march (PR #116707)

[Eli Friedman via cfe-commits]

efriedma-quic wrote:

> Ah, interesting, any objection to not adding the detection macros?

For the feature names, I think we also try to coordinate with Arm to define the names.  (Maybe also in the ACLE? Not sure.)  So I don't object to splitting the patch, but I'm not sure that really helps.

https://github.com/llvm/llvm-project/pull/116707