galil: stop spurious begin error on very small moves

The galil driver, after a move has been requested, checks the BG variable to see if it has started. If the move is very small it may complete so quickly that the driver will never see BG indicate a move in progress and so will flag a begin failure. That this is not a failure can be seem by
- stop code reported is 1 (motor reached independene commadn position)
- checking current position shows it moved.

## acceptance criteria

- check enhanced to not report spurious move errors
-