Return 0 if FB is not ready.
Return 0 if FB is not ready.

* Fix bug introduced in last commit.

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