feature: add support for rp2350

[deadprogram]

This PR adds support for the rp2350.

I tested on a pico2 with the ws2812b example and it worked as expected.

Note that the tests fail due to needing to add the PWM support for rp2350 with tinygo-org/tinygo#4728 for example.

[eliasnaur]

I assume this is initial support? The rp2350 adds another PIO block and adds new opcodes (MOV to/from RX FIFO) among other things.

[deadprogram]

I assume this is initial support? The rp2350 adds another PIO block and adds new opcodes (MOV to/from RX FIFO) among other things.

perhaps you would like to submit a followup PR to this one that adds those? 😍