wl1251: hack to disable filters for fixing association

Commit 9cef8737

 "mac80211: fix managed mode BSSID handling" broke
association in wl1251, most probably because the driver configured
the bssid filter incorrectly. Workaround this by disabling filter
altogether. This needs to be fixed properly soon.

Signed-off-by: Kalle Valo <kalle.valo@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>