wifi: support 802.11k and 802.11v

[nagyrobi]

Do we support these?
Idea from: esphome/esphome#3600

[fvanroie]

Support for these Wifi features were added in ESP-IDF 4.4. I see that the flags are present in Arduino 2.0 but are not exposed.
The Wifi.connect() method does not allow these parameters to be set yet from Arduino.

Either the flags need to be added to the Arduino Wifi library, or a custom connect method needs to be implemented like ESPhome...

[fvanroie]

The support for these are very new. I found a roaming example for ESP-IDF: roaming_example.c
However, some of the functions used are not yet in the latest Tasmota Core 2.0.4pre with ESP-IDF v4.4.1.1.

From what I gather RRM (802.11k) might be possible without custom code, but BTM (802.11v) requires application code to activate re-scanning and select an alternate AP when the RRSI drops below a certain threshold. I would expect this could/should be handled best by the Arduino Core, so all sketches can benefit from this feature... But Arduino Core is lacking this atm.

[nagyrobi]

Understood, thanks for looking after.

[fvanroie]

I added a feature/wifi branch that enables both flags via the ESP-IDF commands. Not sure if this is enough, but the WiFi stack reports them as enabled now (disabled by default):

[       4.107][86004/100272 14][53128/53132  1] WIFI: Connected to test, requesting IP...
[       4.129][86004/99692 13][53128/53132  1] WIFI: BTM: Enabled
[       4.141][86004/100032 14][53128/53132  1] WIFI: RM : Enabled
[       4.153][86004/100180 14][53128/53132  1] WIFI: Received IP address 192.168.1.123
[       4.167][86004/100180 14][53128/53132  1] ----: Connected = online

I don't know how to test/verify the features properly, so you might want to do some testing in your network first.