AP_NavEKF2: Update comments for filter status output function

libraries/AP_NavEKF2/AP_NavEKF2_Outputs.cpp

@@ -377,15 +377,11 @@ void  NavEKF2_core::getFilterTimeouts(uint8_t &timeouts) const
 }
 
 /*
-return filter function status as a bitmasked integer
- 0 = attitude estimate valid
- 1 = horizontal velocity estimate valid
- 2 = vertical velocity estimate valid
- 3 = relative horizontal position estimate valid
- 4 = absolute horizontal position estimate valid
- 5 = vertical position estimate valid
- 6 = terrain height estimate valid
- 7 = constant position mode
+Return a filter function status that indicates:
+    Which outputs are valid
+    If the filter has detected takeoff
+    If the filter has activated the mode that mitigates against ground effect static pressure errors
+    If GPS data is being used
 */
 void  NavEKF2_core::getFilterStatus(nav_filter_status &status) const
 {

libraries/AP_NavEKF2/AP_NavEKF2_core.h

@@ -194,7 +194,11 @@ public:
     void  getFilterTimeouts(uint8_t &timeouts) const;
 
     /*
-    return filter status flags
+    Return a filter function status that indicates:
+        Which outputs are valid
+        If the filter has detected takeoff
+        If the filter has activated the mode that mitigates against ground effect static pressure errors
+        If GPS data is being used
     */
     void  getFilterStatus(nav_filter_status &status) const;