[llvm] r174054 - Add AArch64 as an experimental target.

[Tim Northover]

> llvm/trunk/test/CodeGen/AArch64/logical_shifted_reg.s   (with props)
>
> Was added? It looks like it's just a remnant from running tests
> manually, perhaps

I think so too, I've fixed it in r184236.

Thanks.

Tim