hostapd: add IEEE 802.11k support

Enables radio resource management to be reported by hostapd to clients.

Ref: https://github.com/lede-project/source/pull/1430
Co-developed-by: Lorenzo Santina <lorenzo.santina@edu.unito.it>
Signed-off-by: Lorenzo Santina <lorenzo.santina@edu.unito.it>
Signed-off-by: Kyle Copperfield <kmcopper@danwin1210.me>
[removed the DMARC crap]
Signed-off-by: Petr Štetiar <ynezz@true.cz>
(cherry picked from commit 87f9292300cf56ad17f44363ced213c59a95ef44)

package/network/services/hostapd/files/hostapd.sh

@@ -223,6 +223,8 @@ hostapd_common_add_bss_config() {
 	config_add_int time_advertisement
 	config_add_string time_zone
 
+	config_add_boolean ieee80211k rrm_neighbor_report rrm_beacon_report
+
 	config_add_boolean ieee80211r pmk_r1_push ft_psk_generate_local ft_over_ds
 	config_add_int r0_key_lifetime reassociation_deadline
 	config_add_string mobility_domain r1_key_holder
@@ -489,6 +491,17 @@ hostapd_set_bss_options() {
 		append bss_conf "bss_transition=$bss_transition" "$N"
 	fi
 
+	json_get_vars ieee80211k
+	set_default ieee80211k 0
+	if [ "$ieee80211k" -eq "1" ]; then
+		json_get_vars rrm_neighbor_report rrm_beacon_report
+
+		set_default rrm_neighbor_report 1
+		set_default rrm_beacon_report 1
+		append bss_conf "rrm_neighbor_report=$rrm_neighbor_report" "$N"
+		append bss_conf "rrm_beacon_report=$rrm_beacon_report" "$N"
+	fi
+
 	if [ "$wpa" -ge "1" ]; then
 		json_get_vars ieee80211r
 		set_default ieee80211r 0