WDS stopped working in 21.02, bug is now fixed in netifd master

[Daniel Haid]

Hello everyone,

I have made the bug reproducible by adding sleep(2) between the calls to 
nl80211_create_iface and linux_br_add_if in src/drivers/driver_nl80211.c 
of hostapd.

In that way, I was able to observe (without the confusing random 
effects) that commit 4d0c2ad3fd268388b97af0582baa8a89c3639d8b in netifd 
master has fixed the bug.

Thank you.

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D.H.