Support both relative and absolute FOLL_ALT_TYPE

src/AutoPilotPlugins/APM/APMFollowComponent.qml

@@ -49,13 +49,15 @@ SetupPage {
             property int  _followComboMaintainIndex:    0
             property int  _followComboSpecifyIndex:     1
             property bool _followMaintain:              followPositionCombo.currentIndex === _followComboMaintainIndex
-            property bool _isFollowMeSetup:             _followEnabled.rawValue == 1 && _followParamsAvailable && _followOffsetType.rawValue == 1 && (_roverFirmware || (!_roverFirmware && _followAltitudeType.rawValue == 1)) && _followSysId.rawValue == 0
+            property bool _isFollowMeSetup:             _followEnabled.rawValue == 1 && _followParamsAvailable && _followOffsetType.rawValue == _followOffsetTypeHeadingRelative && _followSysId.rawValue == 0
             property bool _roverFirmware:               controller.roverFirmware
 
-            readonly property int _followYawBehaviorNone:   0
-            readonly property int _followYawBehaviorFace:   1
-            readonly property int _followYawBehaviorSame:   2
-            readonly property int _followYawBehaviorFlight: 3
+            readonly property int _followYawBehaviorNone:           0
+            readonly property int _followYawBehaviorFace:           1
+            readonly property int _followYawBehaviorSame:           2
+            readonly property int _followYawBehaviorFlight:         3
+            readonly property int _followOffsetTypeHeadingRelative: 1
+            readonly property int _followAltitudeTypeRelative:      1
 
             Component.onCompleted: _setUIFromParams()
 
@@ -89,7 +91,7 @@ SetupPage {
                 _followOffsetType.rawValue =    1   // Relative to vehicle
                 _followSysId.rawValue =         0   // Follow first message sent
                 if (!_roverFirmware) {
-                    _followAltitudeType.rawValue = 1   // Altitude is relative
+                    _followAltitudeType.rawValue = _followAltitudeTypeRelative
                 }
 
                 controller.distance.value = controller.distance.defaultValue