Support extra metrics in the RDC

Remove the * in the rdci stats
When a group is created, the GPUs can be added in the same command.
Add the support to the memory temperature.
Add the support to the memory clock.
Add the support to report the ECC errors.
Add the support to report the PCIe bandwidth throughput.

Since the RX/TX throughput may take 1 second to retreive, an async fetch is implemented
in the RdcMetricFetcherImpl.

Change-Id: If04f602fe1f2d14dbf7c2fb189549fd030523f9a

include/rdc_lib/impl/RdcEmbeddedHandler.h

@@ -92,6 +92,7 @@ class RdcEmbeddedHandler: public RdcHandler {
     ~RdcEmbeddedHandler();
 
  private:
+    rdc_status_t get_gpu_gauges(rdc_gpu_gauges_t* gpu_gauges);
     RdcGroupSettingsPtr group_settings_;
     RdcCacheManagerPtr cache_mgr_;
     RdcMetricFetcherPtr metric_fetcher_;