Add enable/disable external OSC callback functions.
Add enable/disable external OSC callback functions.

iabdalkader/openmv,kwagyeman/openmv,openmv/openmv,kwagyeman/openmv,kwagyeman/openmv,openmv/openmv,iabdalkader/openmv,openmv/openmv,openmv/openmv,iabdalkader/openmv,iabdalkader/openmv,kwagyeman/openmv