hostapd: Add fix for HE40 mode on 2.4G
HE40 issues on 2.4G was already solved in upstream hostapd. Because we still base on older hostapd version that do not has this fix, let's just cherry-pick it here. Later when we update hostapd this patch (9190-ACS-Allow-downgrading-to-20-MHz-based-on-OBSS-result.patch) can be removed.
Signed-off-by: Marek Puzyniak marek.puzyniak@iopsys.eu