mac80211: accept deauth frames in IBSS mode

We can process deauth frames and all, but we drop them very
early in the RX path today - this could never have worked.

Fixes: 2cc59e78 ("mac80211: reply to AUTH with DEAUTH if sta allocation fails in IBSS")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/20191004123706.15768-2-luca@coelho.fi


Signed-off-by: Johannes Berg <johannes.berg@intel.com>