Avoid potential ADL ambiguity between llvm::make_unique and std::make_unique (when building as C++14+)

Patch by Moritz Kiefer!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298266 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed