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

[Paul Walker via cfe-commits]

paulwalker-arm wrote:

> This intrinsic is only a month old so adding an auto upgrade might be an overkill. What do you think ?

Personally I also think it's overkill but I guess the reasoning is there will always be a version of LLVM that supports the dodgy intrinsic out there in the world, so any later version of LLVM needs to be able to handle the bitcode the former can create.

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