update EKF failsafe actions

Author: Hwurzburg

copter/source/docs/ekf-inav-failsafe.rst

@@ -27,7 +27,7 @@ What will happen when the failsafe triggers?
 - The autopilot's `LED will flash red-yellow or blue-yellow and the tone-alarm will sound <https://www.youtube.com/watch?v=j-CMLrAwlco&feature=player_detailpage&t=60s>`__
 - "EKF variance" will appear on the ground station's HUD if telemetry is connected
 - In manual flight modes that do not require GPS (i.e. Stabilize, Acro, AltHold) nothing further will happen but the pilot will be unable to switch into autonomous flight modes (Loiter, PosHold, RTL, Guided, Auto) until the failure clears
-- In autonomous modes that require GPS (i.e. Loiter, PosHold, RTL, Guided, Auto, etc) the :ref:`FS_EKF_ACTION <FS_EKF_ACTION>` controls the behaviour.  By default this is "1" meaning the vehicle will switch to :ref:`Land <land-mode>` mode.  This is a "pilot controlled" land meaning the pilot will have control of the roll and pitch angle but the vehicle will descend at the :ref:`LAND_SPEED <LAND_SPEED>`.  It will land and finally disarm its motors
+- In autonomous modes that require GPS (i.e. Loiter, PosHold, RTL, Guided, Auto, etc) the :ref:`FS_EKF_ACTION <FS_EKF_ACTION>` controls the behaviour.  By default this is "1" meaning the vehicle will switch to :ref:`Land <land-mode>` mode.  This is a "pilot controlled" land meaning the pilot will have control of the roll and pitch angle but the vehicle will descend at the :ref:`LAND_SPEED <LAND_SPEED>`.  It will land and finally disarm its motors. Other options are to hover (ALTHOLD) or LAND even if in STABILIZE mode if the EKF failsafe occurs.
 - An EKF failsafe error will be written to the dataflash logs
 
 After an EKF failsafe occurs, the pilot can re-take control (using the flight mode switch) in a manual flight mode such as :ref:`AltHold <altholdmode>` to bring the vehicle home.