RP2: Don't build sensor.c if it's disabled.
RP2: Don't build sensor.c if it's disabled.

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