[PATCH] mac80211: fail back to use associate from reassociate

Some APs have strict checking between associate and reassociate. In
a case when an AP is restarted during a connection, it denies the
mac80211 reassoc request since this is a new association for the AP.
To fix this problem, we need to check the status code against
WLAN_STATUS_REASSOC_NO_ASSOC and clear ifsta->prev_bssid_set in
handling the association failure response.

Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>