Deactivate OpenFlow in P4-Trellis STC scenario
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

opennetworkinglab/onos,oplinkoms/onos,oplinkoms/onos,gkatsikas/onos,oplinkoms/onos,opennetworkinglab/onos,oplinkoms/onos,oplinkoms/onos,oplinkoms/onos,opennetworkinglab/onos,gkatsikas/onos,gkatsikas/onos,oplinkoms/onos,gkatsikas/onos,gkatsikas/onos,opennetworkinglab/onos,opennetworkinglab/onos,gkatsikas/onos,opennetworkinglab/onos