RDC module framework

The framework is required for RAS integration. When the RAS fields
need to be retrieved, the framework will load the RAS library at run time,
and then call the RAS function to retrieve RAS metrics.

* The RdcModuleMgr will be used to manage different modules. RDC
  only has the telemetry module now.
* When RDCTelemetryModule is loaded, it will load the RAS library.
  It will also call rdc_telemetry_fields_query() defined in the RAS
  library for the list of fields RAS supported.
* The RdcSmiLib is a wrapper for the rocm_msi_lib to provide the
  interface required by the RDCTelemetryModule.
* The RdcWatchTable will use the RdcModuleMgr to get the
  RDCTelemetryModule to bulk fetch mulitple fields.
* The RdcTelemetryModule will dispatch those fields to different
  library: RdcSmiLib or RdcRasLib.

The watch() and unwatch() in the RDCTelemetryModule will been implemented
at the next task.

Change-Id: I81b01d5b52d1ea3cdcec7c09af86b6622dd5899e

rdc_libs/bootstrap/src/RdcLibraryLoader.cc

@@ -28,6 +28,25 @@ namespace rdc {
 RdcLibraryLoader::RdcLibraryLoader(): libHandler_(nullptr) {
 }
 
+rdc_status_t RdcLibraryLoader::load(const char* filename) {
+    if (filename == nullptr) {
+        return RDC_ST_FAIL_LOAD_MODULE;
+    }
+    if (libHandler_) {
+        unload();
+    }
+
+    std::lock_guard<std::mutex> guard(library_mutex_);
+    libHandler_ = dlopen(filename, RTLD_LAZY);
+    if (!libHandler_) {
+        char* error = dlerror();
+        RDC_LOG(RDC_ERROR, "Fail to open " << filename <<": " << error);
+        return RDC_ST_FAIL_LOAD_MODULE;
+    }
+
+    return RDC_ST_OK;
+}
+
 rdc_status_t RdcLibraryLoader::unload() {
         std::lock_guard<std::mutex> guard(library_mutex_);
         if (libHandler_) {