ios: improve automatic kits

* fix incorrect old kits
* avoid adding a special debugger

Change-Id: I233068dbb9958045cdc2e875337297748b2b4ff8
Reviewed-by: hjk <hjk121@nokiamail.com>
Reviewed-by: Fawzi Mohamed <fawzi.mohamed@digia.com>

src/plugins/debugger/debuggeritemmanager.h

@@ -62,6 +62,7 @@ public:
 
     static const DebuggerItem *findByCommand(const Utils::FileName &command);
     static const DebuggerItem *findById(const QVariant &id);
+    static const DebuggerItem *findByEngineType(DebuggerEngineType engineType);
 
     static void restoreDebuggers();
     static QString uniqueDisplayName(const QString &base);