* uci state was not getting reset properly during teardown
* AP+STA co-exist state was not flushed properly upon channel switch
* remove a debug logger call
* properly teardown supplicant instances when they get disabled
* add md5 config support for supplicant
* don't call wpa_supplicant_prepare_interface twice
Signed-off-by: John Crispin <john@phrozen.org>