mac80211: Do not request FIF_BCN_PRBRESP_PROMISC for HW scan.

ieee80211_configure_filter code used local->scanning as a boolean
value when it was a bit mask. Bits SCAN_COMPLETED, SCAN_ABORTED
should not set FIF_BCN_PRBRESP_PROMISC filter.

SCAN_HW_SCANNING should not set FIF_BCN_PRBRESP_PROMISC either,
as there is no explicit filter configuration request from
scan code. If a driver requires FIF_BCN_PRBRESP_PROMISC mode
during HW scanning, it's up to the driver to temporary enable it.

Similar mistake was fixed also in ieee80211_hw_config (power
configuration code).

Verified-by: Vitaly Wool <vitaly.wool@sonyericsson.com>
Signed-off-by: Dmitry Tarnyagin <dmitry.tarnyagin@stericsson.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>