Fix --password in server rebuild

Use correct attribute to get password in server rebuild command.

Fixes bug 1190722

Change-Id: Ibe2ccb8840a385319781885b8aadca6e1ba4cc43

Author: Dean Troyer

openstackclient/compute/v2/server.py

@@ -521,8 +521,8 @@ def take_action(self, parsed_args):
             compute_client.servers, parsed_args.server)
 
         _password = None
-        if parsed_args.rebuild_password is not False:
-            _password = parsed_args.rebuild_password
+        if parsed_args.password is not False:
+            _password = parsed_args.password
 
         kwargs = {}
         server = server.rebuild(image, _password, **kwargs)