[portsorch]: Only add stat IDs that are needed to query (sonic-net#396)

The hardcoded for loop was not the good option to query all
IDs defined in the SAI header. While only limited partial of
the counters are needed, we don't need to query each of them.

Signed-off-by: Shu0T1an ChenG <shuche@microsoft.com>

Author: Shuotian Cheng

orchagent/portsorch.cpp

@@ -39,6 +39,14 @@ static map<string, sai_port_fec_mode_t> fec_mode_map =
     { "fc", SAI_PORT_FEC_MODE_FC }
 };
 
+static const vector<sai_queue_stat_t> queueStatIds =
+{
+    SAI_QUEUE_STAT_PACKETS,
+    SAI_QUEUE_STAT_BYTES,
+    SAI_QUEUE_STAT_DROPPED_PACKETS,
+    SAI_QUEUE_STAT_DROPPED_BYTES
+};
+
 /*
  * Initialize PortsOrch
  * 0) By default, a switch has one CPU port, one 802.1Q bridge, and one default
@@ -1498,9 +1506,9 @@ void PortsOrch::initializeQueues(Port &port)
 
         std::string delimiter = "";
         std::ostringstream counters_stream;
-        for (int cntr = SAI_QUEUE_STAT_PACKETS; cntr <= SAI_QUEUE_STAT_SHARED_WATERMARK_BYTES ; ++cntr)
+        for (auto it = queueStatIds.begin(); it != queueStatIds.end(); it++)
         {
-            counters_stream << delimiter << sai_serialize_queue_stat(static_cast<sai_queue_stat_t>(cntr));
+            counters_stream << delimiter << sai_serialize_queue_stat(*it);
             delimiter = ",";
         }