Implement remote LNA toggle CLI command

[jbrazio]

Refactor of #1164.

This pull request adds support for configuring and persisting RX boosted gain settings for SX12xx series radios (SX1262, SX1268, SX1276) across the codebase. These settings are now stored in preferences, can be set and queried via CLI commands, and are applied during radio initialization.

You might hang a repeater [with a proper antenna] in a difficult to access place to find out that there is a lot of QRM and RX is deaf; most of the situations where I faced this, disabling the Boosted Gain helped a lot with the problem.

When we use small out-of-tune antennas (the ones shipping with the boards) having a boost on the RX helps, this is usually the client situation. For repeater where we usually have proper antennas it's a question of testing with it ON and OFF and check what gives you better performance.

[JDat]

Idea looks good, but... Can this be done without reconfiguring every platform? Let's say: every board/target have function to control LNA boost and... Depending on platform, LNA boost gain setting is transfered to radio chip. If board/platform/variant not support LNA Boss, it just do noting (empty function). This approach allow to write code without zillion of #define-s

[jbrazio]

Yeah I know it's a lot of duplicated code but due to the current architecture the requirement of having the function prototypes on target.cpp/h will not go away, having them as empty pointers or adding a conditional macro.. depends on the coding style. And the current coding style is to use conditional macros.

[towerviewcams]

The boost in the SX12xx board with large amounts of testing does not effect RX sensitivity or noise floor. We tested this allot with the V4 and the LNA bypassed with PCB jump wire. Then set the boost flag on and off on the SX12xx......There was no difference we could find in both quiet and noisy locations. This was for the Sx1262 in the V4.

If someone can really see a difference with this, what board are you using? Our group hasn't been able to duplicate that.

Using the term LNA might confuse people into thinking its the external 17db LNA that cannot be controlled by software. This is what happen in PR1398 at first.

[jbrazio]

We had a couple of cases with WSL3 and T114 (433 band) in really good city center spots where the TX had a good coverage but RX was just deaf. Uploading a firmware with the LNA off solved the issue.

The ideia is exactly that, put the repeater in a high place and test with and without.. then choose what better works for you.

[towerviewcams]

Yea, 433, different world for sure and not V4 as expected - different hardware. Cool