Getting the serial number of the control board

[Combinator78]

Could you please add the serial number extraction of the control board where possible for the devices L7, S19K pro, S21, T21. This is convenient for equipment accounting, since it coincides with the number pasted on the body of the device.

[b-rowan]

Not sure where to source this information for most miners. It might be exposed by whatsminers, but for pretty much anything else I wouldn't know where to even start.

Like the idea, but likely not feasible...