Clang/ClangTools: Separate custom diagnostic configs

Add a separate pool of custom diagnostic configs for the
ClangTools plugin. That is, the diagnostic configs in

  Menu: Tools > C++ > Code Model

are not shared anymore with the configs at

  Menu: Tools > Analyzer > ClangTools

On plugin initialization of ClangTools, move tidy/clazy related configs
to ClangTools.

Change-Id: Id06087a58b53e466a3d7bbac669550c5fbe9899d
Reviewed-by: Cristian Adam <cristian.adam@qt.io>
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/plugins/clangtools/clangtoolsutils.h

@@ -26,6 +26,7 @@
 #pragma once
 
 #include <coreplugin/id.h>
+#include <cpptools/clangdiagnosticconfig.h>
 
 #include <QVersionNumber>
 #include <QtGlobal>
@@ -34,6 +35,7 @@ QT_BEGIN_NAMESPACE
 class QString;
 QT_END_NAMESPACE
 
+namespace CppTools { class ClangDiagnosticConfigsModel; }
 namespace Debugger { class DiagnosticLocation; }
 
 namespace ClangTools {
@@ -52,5 +54,9 @@ QString clazyStandaloneExecutable();
 QString shippedClangTidyExecutable();
 QString clangTidyExecutable();
 
+CppTools::ClangDiagnosticConfigsModel diagnosticConfigsModel();
+CppTools::ClangDiagnosticConfigsModel diagnosticConfigsModel(
+    const CppTools::ClangDiagnosticConfigs &customConfigs);
+
 } // namespace Internal
 } // namespace ClangTools