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

[David Green via cfe-commits]

davemgreen wrote:

Could you give more details about why you would want these added? As far as I understand they are mandatory features for 8.4 and 8.7, and would usually be added via -march=armv8.4-a for example. We try to keep the options between GCC and clang the same, and GCC doesn't seem to support either https://godbolt.org/z/TTnq48W81. 

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