Add bcning field in router_config response

[soorajm13]

• I have searched the issues of this repository and believe that this is not a duplicate.

Summary

The bcning is currently not sent in the router_config response.

What is the use-case?

Class B will require enabling bcning support. Tested with the currently released Chirpstack V4 docker, couldn't enable class B beacons and test it.

Example gateway configuration: Chirpstack V4 docker + LoRa basicstation 2.0.6 + sx1302 concentrator

Implementation description

Add bcning field to the LNS response. Update documentation and add news steps for enabling class B beacon support.

Can you implement this by yourself and make a pull request? No

[kairoswater-jason]

I (as an end user) just reached the same conclusion for my own application
While I suspect I could hack my own instance of the bridge to send hard-coded beacon information. It would be better to get the beacon configuration information from chirpstack rather than hardcode it.

[kairoswater-jason]

For my reference, and anyone else's

protocol reference
https://doc.sm.tc/station/tcproto.html

source in basicstation that parses that beaconing field: (which is part of router_config)
https://github.com/lorabasics/basicstation/blob/ba4f85d80a438a5c2b659e568cd2d0f0de08e5a7/src/s2e.c#L1100

example of a configuration used to test basicstation:
https://github.com/lorabasics/basicstation/blob/ba4f85d80a438a5c2b659e568cd2d0f0de08e5a7/regr-tests/test3d-bcns/test.py#L115

conf['bcning'] = {
 'DR': 8,
 'layout': [5,11,23],
 'freqs': [923300000 + chx * 600000 for chx in range(8)] #[923300000, 923900000, 924500000, 925100000, 925700000, 926300000, 926900000, 927500000]



}