Fix debug on Android 6+ with NDK r11+

Task-number: QTCREATORBUG-16721
Change-Id: Ic65f13076794b75d6e4551b68d26fd3752f82098
Reviewed-by: hjk <hjk@qt.io>

src/plugins/debugger/debuggerengine.h

@@ -97,7 +97,6 @@ public:
     QStringList debugSourceLocation; // Gdb "directory"
     QString serverStartScript;
     ProjectExplorer::IDevice::ConstPtr device;
-    QString sysRoot;
     bool isSnapshot = false; // Set if created internally.
     ProjectExplorer::Abi toolChainAbi;