In the tests that only want to iterate over the hostapd interfaces,
simplify the pattern of walking through the whole wiphy_map tree by
instead using the hostapd_map variable which is already filtered to only
contain hostapd interfaces.
The simplest way to test this was to create a new AP, where
max_num_sta=1. This only allows a single STA to connect to this AP.
We connect a device to this AP, then try and connect with another.
This results in hostapd failing with DENIED_NO_MORE_STAS, which will
cause a temporary blacklist. We can then disconnect both devices,
and reconnect the device that previously got denied. If it connects
then we know the blacklist only persisted for that earlier connection.
Andrew Zaborowski