mac80211: fix debugfs default key links
Due to the way the default key links are created,
it happens that a link is left dangling:
* both unicast/multicast links are created
* unicast link is destroyed, and the links
are updated
* during this update, adding the multicast
link again fails because it is present,
destroying the debugfs pointer
* removing the multicast link won't work as
the pointer has been destroyed
Fix this by always removing the links and then
re-creating them if needed.
Reported-by: Marek Lindner <lindner_marek@yahoo.de>
Reported-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>