WARN_ON was triggered at mlme.c:213 when dissociating from an AP.
wdev->current_bss->pub.bssid should be used in place of
wdev->current_bss for BSSID comparison.
Signed-off-by: Pavel Roskin <proski@gnu.org> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>