Fix two error-case unwinders.

Noticed by moto, I missed to calls to actually do the unwinding.

Change-Id: Ie4da4979a3ad0eedcb6d468fecdff6614b1819bd
diff --git a/NatController.cpp b/NatController.cpp
index beba4ce..97b17a1 100644
--- a/NatController.cpp
+++ b/NatController.cpp
@@ -199,6 +199,7 @@
                 "-%s FORWARD -i %s -o %s -m state --state ESTABLISHED,RELATED -j ACCEPT",
                 (!add ? "A" : "D"),
                 extIface, intIface);
+        runIptablesCmd(cmd);
         return -1;
     }
 
@@ -216,6 +217,7 @@
                  "-%s FORWARD -i %s -o %s -m state --state ESTABLISHED,RELATED -j ACCEPT",
                  (!add ? "A" : "D"),
                  extIface, intIface);
+        runIptablesCmd(cmd);
         return -1;
     }