Don't start second scan when changing scan interval

If a scan is currently running and the scan interval is changed, a
second scan will be started before the current has finished. This will
in turn, if no networks are configured, cause wpa_s->state to be
forced to WPA_INACTIVE before the first scan has finished.

Signed-hostap: Pontus Fuchs <pontus.fuchs@gmail.com>

wpa_supplicant/scan.c

@@ -887,8 +887,10 @@ void wpa_supplicant_update_scan_int(struct wpa_supplicant *wpa_s, int sec)
 		new_int.usec = remaining.usec;
 	}
 
-	eloop_register_timeout(new_int.sec, new_int.usec, wpa_supplicant_scan,
-			       wpa_s, NULL);
+	if (cancelled) {
+		eloop_register_timeout(new_int.sec, new_int.usec,
+				       wpa_supplicant_scan, wpa_s, NULL);
+	}
 	wpa_s->scan_interval = sec;
 }