QoS for guest network fails to start on Turris OS 6.0+
Description
If QoS is enabled for guest network, it fails with following error:
turris SQM: ERROR: br-guest_turris does currently not exist, not even trying to start SQM on nothing.
This failure is not detected and shown in reForis anyhow, so user is misled that QoS works fine - however that is not the point of this issue, because once it will be fixed on backend, it will work fine from the (a) reforis and (b) Turris OS point of view.
Why it fails
Currently there is discrepancy between guest network general setup and qos handling code, in particular what should be the guest network bridge name:
br-guest_turris vs br-guest-turris
Proposed solution
Use the same turris guest network bridge name everywhere.