Fix formatting in RTL mode documentation

Author: jinmussj

copter/source/docs/rtl-mode.rst

@@ -12,7 +12,7 @@ to use and customize RTL mode.
 Overview
 ========
 
-When RTL mode is selected, the copter will return to the home location, or if :ref:`rally points <common-rally-points>`  have been setup, the closest rally point.
+When RTL mode is selected, the copter will return to the home location, or if :ref:`rally points <common-rally-points>` have been setup, the closest rally point.
 
 The copter will first rise a minimum of :ref:`RTL_CLIMB_MIN<RTL_CLIMB_MIN>` or to  :ref:`RTL_ALT_M<RTL_ALT_M>`, whichever is higher, before returning home.  The default value for :ref:`RTL_ALT_M<RTL_ALT_M>` is 15m. Under no circumstances will this altitude be below 30cm.