[clang] [llvm] [CGObjC] Allow clang.arc.attachedcall on -O0 (PR #164875)

[John McCall via llvm-commits]

rjmccall wrote:

Okay, what you're saying is that this is now supported in GlobalISel, so we can use it in -O0 on the same architectures that use it for -O? If so, great, let's remove the -O0 condition.

https://github.com/llvm/llvm-project/pull/164875