VCS: Remove reading of very old settings

Change-Id: Id75da5d764c0ea65942c49324c2db6d033cf62a1
Reviewed-by: Orgad Shaneh <orgads@gmail.com>
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/cvs/cvssettings.h

@@ -44,9 +44,6 @@ public:
     int timeOutMs() const;
 
     QStringList addOptions(const QStringList &args) const;
-
-protected:
-    void readLegacySettings(const QSettings *settings) override;
 };
 
 } // namespace Internal