AP_GPS: correct GPS_AUTO_SWITCH parameter description

libraries/AP_GPS/AP_GPS.cpp

@@ -106,7 +106,7 @@ const AP_Param::GroupInfo AP_GPS::var_info[] = {
 #if GPS_MAX_RECEIVERS > 1
     // @Param: _AUTO_SWITCH
     // @DisplayName: Automatic Switchover Setting
-    // @Description: Automatic switchover to GPS reporting best lock, 1:UseBest selects the GPS with highest status, if both are equal the GPS with highest satellite count is used 4:Use primary if 3D fix or better, will revert over 'UseBest' behaviour if 3D fix is lost on primary
+    // @Description: Automatic switchover to GPS reporting best lock, 1:UseBest selects the GPS with highest status, if both are equal the GPS with highest satellite count is used 4:Use primary if 3D fix or better, will revert to 'UseBest' behaviour if 3D fix is lost on primary
     // @Values: 0:Use primary, 1:UseBest, 2:Blend, 4:Use primary if 3D fix or better
     // @User: Advanced
     AP_GROUPINFO("_AUTO_SWITCH", 3, AP_GPS, _auto_switch, (int8_t)GPSAutoSwitch::USE_BEST),