Parameter update - Rename variables in modules/navigator

src/modules/navigator/datalinkloss.cpp

src/modules/navigator/datalinkloss.h

src/modules/navigator/follow_target.cpp

src/modules/navigator/follow_target.h

src/modules/navigator/geofence.cpp

src/modules/navigator/geofence.h

src/modules/navigator/gpsfailure.cpp

src/modules/navigator/gpsfailure.h

src/modules/navigator/mission.cpp

src/modules/navigator/mission.h

src/modules/navigator/navigator.h

src/modules/navigator/navigator_main.cpp

src/modules/navigator/precland.cpp

src/modules/navigator/precland.h

src/modules/navigator/rcloss.cpp

src/modules/navigator/rcloss.h

src/modules/navigator/rtl.cpp

src/modules/navigator/rtl.h