Control: add a flag to indicate a submodule was not previously run

Some conditions should be handled when passing control from one mode
to another.  Possibly later this should be replaced with either
passing the previously active control mode to the submodule or
alternatively having a method called when a controller is not
used to allow it to do specific processing.
Tablet Control: use the reset_controller flag to update positions

Previously when toggling into tablet control with position hold or
land the position was only grabbed on the first entry.  This could
result in using a stable position setpoint.
Table Control: Position hold behaves like normal switch

Grab the current altitude as the setpoint, and not a hardcoded value.
Control: make sure position hold always grabs current location

When moving from another tablet mode that uses position hold (e.g.
followme) to position hold ensure the current location is used
instead of the previous behavior which was to leave the pathdesired
unchanged.
Control: fix for cc path

I forgot to update that #ifdef'd function
Merge pull request #454 from peabody124/control_unused

Control: add a flag to indicate a submodule was not previously run