* Add RAK3401 variant files
* Add SPI configuration for RAK3401 and RAK13302 variants
* Refactor SPI pin configuration and clean up variant definitions for RAK3401
* Add TX_GAIN_LORA for RAK13302 Power Amp
* Fix merge
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Co-authored-by: Ben Meadors <benmmeadors@gmail.com>
Co-authored-by: Tom Fifield <tom@tomfifield.net>
Co-authored-by: Manuel <71137295+mverch67@users.noreply.github.com>
