Well you can start by using a "Get Position" action on your Gameobject and setting it to world space and every frame. You will have to save this to a vector 3 var. You would also need to put an empty Gameobject at your desired location and get its world position just like your main object. You can do this all in the same FSM state.
Now if you look in your vector3 action browser there is a "vector3 operator" action. Select this and supply your two vector 3 variables and choose distance. save this to a float var and when it reaches zero you should be there.
Actually I think you can just set the 2nd vector 3 coordinates (0,0,5) in the operator action with no need to get an empties position.