Deactivate OpenFlow in P4-Trellis STC scenario

Some times jobs fail because of an exception in the OpenFlow subsystem
that looks like caused by an external OpenFlow switch trying to connect
to our ONOS instances. Also deactivated GUI since it;s not needed.

Change-Id: I4b8a99575561ce897035db658227d839a4180cef
diff --git a/tools/test/scenarios/net-setup-trellis-p4.xml b/tools/test/scenarios/net-setup-trellis-p4.xml
index 0818668..bd430b6 100644
--- a/tools/test/scenarios/net-setup-trellis-p4.xml
+++ b/tools/test/scenarios/net-setup-trellis-p4.xml
@@ -43,6 +43,12 @@
             <step name="App-Deactivate-RouteService"
                   exec="onos ${OCI} app deactivate org.onosproject.route-service"
                   requires="Trellis-Net-P4-Setup.Initial-Summary-Check"/>
+            <step name="App-Deactivate-OpenFlow"
+                  exec="onos ${OCI} app deactivate org.onosproject.openflow"
+                  requires="Trellis-Net-P4-Setup.Initial-Summary-Check"/>
+            <step name="App-Deactivate-Gui"
+                  exec="onos ${OCI} app deactivate org.onosproject.gui2"
+                  requires="Trellis-Net-P4-Setup.Initial-Summary-Check"/>
         </group>
 
         <!-- Active required apps -->