ONOS-6561 BMv2 handshaker via P4Runtime

+ support fort device-specific default pipeconf
+ improvements to P4runtime and gRPC protocol stuff

Change-Id: I8986fce3959df564454ea3d31859860f61eabcae
diff --git a/drivers/bmv2/src/main/resources/bmv2-drivers.xml b/drivers/bmv2/src/main/resources/bmv2-drivers.xml
index bc343e0..0120974 100644
--- a/drivers/bmv2/src/main/resources/bmv2-drivers.xml
+++ b/drivers/bmv2/src/main/resources/bmv2-drivers.xml
@@ -20,6 +20,8 @@
                    impl="org.onosproject.drivers.bmv2.Bmv2Handshaker"/>
         <behaviour api="org.onosproject.net.packet.PacketProgrammable"
                    impl="org.onosproject.drivers.bmv2.Bmv2PacketProgrammable"/>
+        <behaviour api="org.onosproject.net.pi.model.PiPipelineProgrammable"
+                   impl="org.onosproject.drivers.bmv2.Bmv2PipelineProgrammable"/>
     </driver>
 </drivers>