r221222 - [llvm-api-change] Use findProgramByName.

[Rafael Espíndola]

> -    std::string P(llvm::sys::FindProgramByName(TargetSpecificExecutable));
> -    if (!P.empty())
> -      return P;
> +    auto P = llvm::sys::findProgramByName(TargetSpecificExecutable);
> +    if (P)
> +      return *P;
>    }

It is probably better to write out the type.

Cheers,
Rafael