swss: Fix egress queue counters in voq systems. (#2705)

* In voq systems, the buffer profiles are defined on sysports.  So the
    phy ports do not have buffer queue config and queuesStateVector
    built by getQueueConfigurations in flexcounterorch never has phy
    ports in voq systems. So in voq systems, always enable egress queue
    counters.

orchagent/portsorch.cpp

@@ -6126,6 +6126,16 @@ void PortsOrch::generateQueueMapPerPort(const Port& port, FlexCounterQueueStates
         }
         else
         {
+            // In voq systems, always install a flex counter for this egress queue
+            // to track stats. In voq systems, the buffer profiles are defined on
+            // sysports. So the phy ports do not have buffer queue config. Hence
+            // queuesStateVector built by getQueueConfigurations in flexcounterorch
+            // never has phy ports in voq systems. So always enabled egress queue
+            // counter on voq systems.
+            if (gMySwitchType == "voq")
+            {
+               addQueueFlexCountersPerPortPerQueueIndex(port, queueIndex, false);
+            }
             queuePortVector.emplace_back(id, sai_serialize_object_id(port.m_port_id));
         }
     }