[FS#605] LuCI wireless associated stations doesn't show noise dbm in some channels (5 GHz @ AC 80 MHz width)

[LEDE Bugs]

A new Flyspray task has been opened.  Details are below. 

User who did this - howl (howl) 

Attached to Project - LEDE Project
Summary - LuCI wireless associated stations doesn't show noise dbm in some channels (5 GHz @ AC 80 MHz width)
Task Type - Bug Report
Category - Base system
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - Low
Priority - Very Low
Reported Version - Trunk
Due in Version - Undecided
Due Date - Undecided
Details - With an Archer C7 v2 the list shows up the noise level in the associated stations doesn't show up, instead it shows 0dBm and the bar icon shows empty bars. The noise level is display correctly inside the wifi configuration under the device options.

This only happens at least with the channel 112, I have tried all the channels below from 36-104 (44 and 108 jumps to 48 and 112 respectively because other nearly stations).

Can't try the 4 channels above because radars and the next 4 above because in my country doesn't exist channel 144.

I will try to test with less width than 80 MHz.

I set it to low because it seems that it only affect to the associated stations tables visualization and the wifi network works as it should.

More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=605