auto-t: iwd.py: allow renaming in copy_to_storage

By providing a 'name' keyword argument the file copied will be
renamed to that.

autotests/util/iwd.py

@@ -1152,11 +1152,14 @@ class IWD(AsyncOpAbstract):
         fo.close()
 
     @staticmethod
-    def copy_to_storage(source, storage_dir=IWD_STORAGE_DIR):
+    def copy_to_storage(source, storage_dir=IWD_STORAGE_DIR, name=None):
         import shutil
 
         assert not os.path.isabs(source)
 
+        if name:
+            storage_dir += '/%s' % name
+
         shutil.copy(source, storage_dir)
 
     @staticmethod