Move C++ code out of the C headers and into either C++ headers

or the C++ files themselves. This enables people to use
just a C compiler to interoperate with LLVM.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180063 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Linker/LinkModules.cpp

@@ -12,6 +12,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Linker.h"
+#include "llvm/Wrap.h"
 #include "llvm-c/Linker.h"
 #include "llvm/ADT/DenseSet.h"
 #include "llvm/ADT/Optional.h"