r208868 - AArch64: update test after LLVM CodeGen change

[Tim Northover]

> Any chance of fixing this test to split the frontend and backend
> appropriately - so the backend is tested in LLVM and the frontend in
> Clang? (ie: test IR output in Clang, and LLVM->asm in LLVM)

It's been on my list of annoyances for quite a while. In many cases
they don't even pretend to check argument structure, just that some
vaguely sane instruction is emitted.

But it's probably not going to happen until at least the merge is
done. Even then the actual frequency of breakage isn't very high and
the work in rewriting them properly *is*, so it might take a while
until I get around to it.

Tim.