[clang] [llvm] Remove __arm_atomic_store_with_stshh from llvm (PR #192419)

[Eli Friedman via cfe-commits]

efriedma-quic wrote:

This sounds like the same issue discussed in https://reviews.llvm.org/D153932 ?  We should fix that.

https://github.com/llvm/llvm-project/pull/192419