live: unicast-direct does not validate checksum

this restore method is unreliable, add warning to the logs.

src/live/ogOperations.py

@@ -217,6 +217,7 @@ class OgLiveOperations:
             if os.access(f'/opt/opengnsys/images', os.R_OK) == False:
                 raise OgError('Cannot access /opt/opengnsys/images in read mode, check permissions')
 
+            logging.warn(f'Checksum validation is *NOT* available with UNICAST-DIRECT!')
             image_path = f'/opt/opengnsys/images/{name}.img'
 
         self._restore_image(image_path, devpath)