[llvm-dev] DIGlobalVariableExpression doc in langref

[Adrian Prantl via llvm-dev]

> On Jan 20, 2019, at 1:52 PM, David Blaikie <dblaikie at gmail.com> wrote:
> 
> Adrian - looks like LangRef didn't get updated when DIGlobalVariableExpression was introduced - could you add a little info there?

Done in r351837.

-- adrian