Update wpa_s->current_ssid->frequency on CS event

Update wpa_s->current_ssid->frequency when EVENT_CH_SWITCH is received.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
diff --git a/wpa_supplicant/ap.c b/wpa_supplicant/ap.c
index ce09c57..16ebfaf 100644
--- a/wpa_supplicant/ap.c
+++ b/wpa_supplicant/ap.c
@@ -1205,6 +1205,8 @@
 		return;
 
 	wpa_s->assoc_freq = freq;
+	if (wpa_s->current_ssid)
+		wpa_s->current_ssid->frequency = freq;
 	hostapd_event_ch_switch(wpa_s->ap_iface->bss[0], freq, ht, offset, width, cf1, cf1);
 }