Setup DMA transfer for GPS

[wiktorwieclaw]

GPS will frequently trigger interrupts because there is a constant stream of data. This will waste precious CPU cycles. We could use DMA to speed up it a bit.

Useful resources

• https://dev.to/apollolabsbin/stm32f4-embedded-rust-at-the-hal-dma-controllers-daf
• https://docs.rust-embedded.org/embedonomicon/dma.html