WDS stopped working in 21.02, looking for bug in netifd

[Daniel Haid]

> Please test if applying this change to netifd fixes the issue.

I am currently building the toolchain for the current snapshot, so I can 
test on the current snapshot.

So far I have only been able to test the patch on 21.02. Since the patch 
does not apply cleanly I tried to versions of the patch.

Version 1:

Apply everything except the line with dev->bpdu_filer = <...>.

With this version, it seems that now the interface is *always* in state 
DOWN after booting and it never works even if manually set to UP.

Version 2:

Apply only the last two hunks of the patch.

With this version, I still get random UP/DOWN behaviour at boot, but now 
"/etc/init.d/network restart" seems to sometimes give me a working state 
with the interface UP and the connection working, which I am quite sure 
I never had before.

But since the whole behaviour has a random element of course I can not 
be 100% sure.

I will try with the snapshot as soon as possible.

D.H.