[VOL-2356]core log_level command line argument should take log level names not int value

Change-Id: Ifc9ca5aa6d2b40e068e0ecad845a788edad0a3a1
diff --git a/rw_core/main.go b/rw_core/main.go
index 71f64f3..e8a7ea6 100644
--- a/rw_core/main.go
+++ b/rw_core/main.go
@@ -223,9 +223,16 @@
 	} else {
 		log.Fatal("HOSTNAME not set")
 	}
+
 	realMain()
+
+	logLevel, err := log.StringToLogLevel(cf.LogLevel)
+	if err != nil {
+		panic(err)
+	}
+
 	//Setup default logger - applies for packages that do not have specific logger set
-	if _, err := log.SetDefaultLogger(log.JSON, cf.LogLevel, log.Fields{"instanceId": instanceID}); err != nil {
+	if _, err := log.SetDefaultLogger(log.JSON, logLevel, log.Fields{"instanceId": instanceID}); err != nil {
 		log.With(log.Fields{"error": err}).Fatal("Cannot setup logging")
 	}
 
@@ -235,7 +242,7 @@
 	}
 
 	// Update all loggers to log level specified as input parameter
-	log.SetAllLogLevel(cf.LogLevel)
+	log.SetAllLogLevel(logLevel)
 
 	//log.SetPackageLogLevel("github.com/opencord/voltha-go/rw_core/core", log.DebugLevel)