iOS: Avoid one use of runconfiguration in IosRunner

Change-Id: If0f1e4a64db692ad373fc73087dd1f5c329a3832
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/ios/iosrunner.h

@@ -83,7 +83,6 @@ private:
 
     IosToolHandler *m_toolHandler = nullptr;
     QString m_bundleDir;
-    QString m_arguments;
     ProjectExplorer::IDevice::ConstPtr m_device;
     IosDeviceType m_deviceType;
     bool m_cppDebug = false;