Remove weird property in JoystickConfig

Adjust fly overlay height
Change minimum Qt version to 5.11+

qgroundcontrol.pro

@@ -15,7 +15,7 @@ exists($${OUT_PWD}/qgroundcontrol.pro) {
 
 message(Qt version $$[QT_VERSION])
 
-!equals(QT_MAJOR_VERSION, 5) | !greaterThan(QT_MINOR_VERSION, 11) {
+!equals(QT_MAJOR_VERSION, 5) | !greaterThan(QT_MINOR_VERSION, 10) {
     error("Unsupported Qt version, 5.12+ is required")
 }
 

src/FlightDisplay/FlightDisplayView.qml

@@ -523,7 +523,7 @@ Item {
             id:                 flyViewOverlay
             z:                  flightDisplayViewWidgets.z + 1
             visible:            !QGroundControl.videoManager.fullScreen
-            height:             mainWindow.height
+            height:             mainWindow.height - mainWindow.header.height
             anchors.left:       parent.left
             anchors.right:      altitudeSlider.visible ? altitudeSlider.left : parent.right
             anchors.bottom:     parent.bottom

src/VehicleSetup/JoystickConfig.qml

@@ -184,9 +184,8 @@ SetupPage {
                             width:              100
                             sourceComponent:    axisMonitorDisplayComponent
 
-                            property real ScreenTools.defaultFontPixelWidth: ScreenTools.defaultFontPixelWidth
-                            property bool mapped:           controller.rollAxisMapped
-                            property bool reversed:         controller.rollAxisReversed
+                            property bool mapped:   controller.rollAxisMapped
+                            property bool reversed: controller.rollAxisReversed
                         }
 
                         Connections {