We no longer use wpa_supplicant for MAC address randomization. Instead, NetworkManager
handles it on it's own. It is actually important that supplicant does not interfere
when setting the MAC address of the device.
The code was only in effect when supplicant has a PreassocMacAddr property.
As this is a recent feature, the left-over code wasn't noticed until now.
https://mail.gnome.org/archives/networkmanager-list/2017-February/msg00003.html
Fixes: 767abfa690
As the fast-supported flag changes, update the existing supplicant
interfaces with the new information.
Also, by default assume it is supported.
(cherry picked from commit 872b9ec5ea)
