[PATCH] UnusedInterface: add forgotten method overide

[Ondrej Lichtner]

From: Ondrej Lichtner

The cleanup method wasn't overridden and the controller would try to
unmap unused interfaces.

Signed-off-by: Ondrej Lichtner 
---
 lnst/Controller/Machine.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lnst/Controller/Machine.py b/lnst/Controller/Machine.py
index cfc4d77..26e475a 100644
--- a/lnst/Controller/Machine.py
+++ b/lnst/Controller/Machine.py
@@ -928,3 +928,6 @@ class UnusedInterface(Interface):

def down(self):
         pass
+
+    def cleanup(self):
+        pass