Incorrect SPI low-level access method for SX126x

[jgromes]

Hey guys,

While updating my station, I noticed tinyGS requires RadioLib godmode to build. Digging further, I noticed the following:

https://github.com/G4lile0/tinyGS/blob/2128f1410cfd229b9b5478a122446e393b41a0a2/tinyGS/src/Radio/Radio.cpp#L172-L175

Couple of thoughts on that:

1. Please don't use godmode in production code, it's supposed to be a development feature. I'm guessing this is some sort of low-level direct hardware access, but as a rule of thumb, if you find yourselves in a situation you need to use it, it might be better to raise an issue in RadioLib repository.
2. You're actually using incorrect SPI method for SX126x. The SPI interface is completely different from SX127x, so you have to use SX126x::writeRegister() instead of Module::SPIsetRegValue(). Also most of SX126x SPI registers are undocmented, and things like modem configuration have to be done through a command-based interface.

Overall, using godmode to achieve this seems like a massive overkill, since it will make literally every single method in the library accessible from the user sketch. I think a macro to selectively enable couple low-level hardware methods would be better here.