Make sure LLVMLoadLibraryPermanently gets an extern "C" symbol.

Otherwise it's impossible to use it. Also don't include C++ headers in
a C header.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194581 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm-c/Support.h

@@ -15,7 +15,6 @@
 #define LLVM_C_SUPPORT_H
 
 #include "llvm-c/Core.h"
-#include "llvm/Support/DynamicLibrary.h"
 
 #ifdef __cplusplus
 extern "C" {

lib/Support/DynamicLibrary.cpp

@@ -19,7 +19,7 @@
 #include "llvm/ADT/StringMap.h"
 #include "llvm/Config/config.h"
 #include "llvm/Support/Mutex.h"
-#include "llvm-c/Core.h"
+#include "llvm-c/Support.h"
 #include <cstdio>
 #include <cstring>