mac80211: clear local->in_reconfig on reconfig error

If reconfiguration fails, local->in_reconfig is never
cleaned, resulting in rx frames being dropped next
time the device is started.

Signed-off-by: Eliad Peller <eliadx.peller@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>