Add support for Raspberry Pi Pico RP2040 board

[cyber-murmel]

Sorry for closing and reopening this PR. I was cleaning up my fork to be forked from this repo.

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This PR provides the files to run apollo on the Raspberry Pi Pico.

Compile with

make APOLLO_BOARD=raspberry_pi_pico

Pin Map

	TMS_GPIO = 5,
	TDI_GPIO = 3, // MOSI
	TDO_GPIO = 4, // MISO
	TCK_GPIO = 6, // SCK

I also got code for other RP2040 boards, but they aren't supported yet in the upstream tinyusb.

[mndza]

Thank you! I added some suggestions.

[cyber-murmel]

I can't reproduce the failed build on my machine.

[cyber-murmel]

The copyright and license notice are currently still very inconsistent. Do you have a preference on what to set them to?

[mossmann]

Thank you so much for the contribution!