Fix H7 DMA region size.
Fix H7 DMA region size.

* Note still need to make the MSC buffer size configurable in MP.

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