ldc 0.15.1 minimal patch to support llvm 3.6.1

[John Colvin via Digitalmars-d-announce]

I need to be able to get ldc 0.15.1 to compile with llvm 3.6.1 
for homebrew. Are there some convenient commits I can use to 
patch it, or is it all a bit more complicated than that?

Also, what's the expected release for 0.15.2? If you expect it to 
be fully released very shortly, this wouldn't be worth doing and 
we'd just wait until then.