Skip EVENT_ACS_CHANNEL_SELECTED also without CONFIG_AP

CONFIG_ACS alone should not refer to wpa_s->ap_iface to avoid potential
compilation issues.

Signed-off-by: Jouni Malinen <j@w1.fi>

wpa_supplicant/events.c

@@ -4319,12 +4319,14 @@ void wpa_supplicant_event(void *ctx, enum wpa_event_type event,
 #endif /* CONFIG_AP */
 		break;
 	case EVENT_ACS_CHANNEL_SELECTED:
+#ifdef CONFIG_AP
 #ifdef CONFIG_ACS
 		if (!wpa_s->ap_iface)
 			break;
 		hostapd_acs_channel_selected(wpa_s->ap_iface->bss[0],
 					     &data->acs_selected_channels);
 #endif /* CONFIG_ACS */
+#endif /* CONFIG_AP */
 		break;
 	case EVENT_P2P_LO_STOP:
 #ifdef CONFIG_P2P