JoystickConfigController: Add missing const in member functions

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

src/VehicleSetup/JoystickConfigController.cc

@@ -714,7 +714,7 @@ void JoystickConfigController::_activeJoystickChanged(Joystick* joystick)
     }
 }
 
-bool JoystickConfigController::_validAxis(int axis)
+bool JoystickConfigController::_validAxis(int axis) const
 {
     return axis >= 0 && axis < _axisCount;
 }

src/VehicleSetup/JoystickConfigController.h

@@ -81,12 +81,12 @@ public:
     bool getDeadbandToggle                  ();
     void setDeadbandToggle                  (bool);
 
-    int  axisCount                          () { return _axisCount; }
+    int  axisCount                          () const{ return _axisCount; }
 
-    int  transmitterMode                    () { return _transmitterMode; }
+    int  transmitterMode                    () const{ return _transmitterMode; }
     void setTransmitterMode                 (int mode);
 
-    bool calibrating                        () { return _currentStep != -1; }
+    bool calibrating                        () const{ return _currentStep != -1; }
     bool nextEnabled                        ();
     bool skipEnabled                        ();
 
@@ -171,7 +171,7 @@ private:
     void _advanceState          ();
     void _setupCurrentState     ();
 
-    bool _validAxis             (int axis);
+    bool _validAxis             (int axis) const;
 
     void _inputCenterWaitBegin  (Joystick::AxisFunction_t function, int axis, int value);
     void _inputStickDetect      (Joystick::AxisFunction_t function, int axis, int value);