Update examples for Feather RP2040 RFM

[PaintYourDragon]

All examples — RFM69 and LoRa — include pin defs for the new RP2040 Feathers. These compile successfully and the RFM69 examples are tested (some Serial strangeness as discussed, but the radio parts work). LoRa are untested (just ordered hardware for this), but as it’s just an equivalent set of pin changes, not expecting any surprises here.

Also some minor reformatting throughout, no functional changes, just y’know how code accumulates unneeded lines and chars and then gets copypasta’d all over the place.

[ladyada]

probably best to remove nRF52832 testing as it doesnt pass CI and not a lot of '832 users