cfg80211: clear wep keys after disconnection

When a low level driver calls cfg80211_disconnected(), wep keys are
not cleared. As a result, following connection requests will fail
since cfg80211 internal state shows a connection is still in progress.

Fix this by clearing the wep keys when disconnecting.

Signed-off-by: Avraham Stern <avraham.stern@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Git-commit: 3027a8e799b20fc922496a12f8ad2f9f36a8a696
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next.git


Change-Id: If86c857b350d3941e016108d44c60ab9b583f7a3
CRs-Fixed: 2229833c
Signed-off-by: Zhu Jianmin <jianminz@codeaurora.org>