wlcore: memset wl->rx_filter_enabled to zero after recovery

zero rx_filter_enabled array after recovery to avoid
cases were the driver will keep trying to clear a
filter which is not configured in FW.

Such case will cause consecutive recoveries due to
command execution failures.

While on it, convert rx_filter_enabled to bitmap,
to save some memory and make sparse happy (it
doesn't like sizeof(bool array)).

Signed-off-by: Nadim Zubidat <nadimz@ti.com>
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>