Adapt compilerplugins to recent Clang trunk change

Change-Id: I3013799433e7b82d6b869e9a3cf071495a12d5ae
Reviewed-on: https://gerrit.libreoffice.org/54304Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

compilerplugins/clang/includeform.cxx

@@ -9,6 +9,8 @@
 
 #include <memory>
 
+#include "config_clang.h"
+
 #include "compat.hxx"
 #include "plugin.hxx"
 
@@ -26,7 +28,11 @@ private:
     void InclusionDirective(
         SourceLocation HashLoc, Token const & IncludeTok, StringRef,
         bool IsAngled, CharSourceRange FilenameRange, FileEntry const * File,
-        StringRef SearchPath, StringRef, clang::Module const *) override
+        StringRef SearchPath, StringRef, clang::Module const *
+#if CLANG_VERSION >= 70000
+        , SrcMgr::CharacteristicKind
+#endif
+        ) override
     {
         if (ignoreLocation(HashLoc)) {
             return;