[VOL-2357]openolt adapter log_level command line argument should take log level names not int value

Change-Id: I63b94c5c546a11a6612f09fec6e0658633c96351
diff --git a/config/config.go b/config/config.go
index b763621..0095575 100644
--- a/config/config.go
+++ b/config/config.go
@@ -37,7 +37,7 @@
 	defaultKvstoretimeout       = 5 //in seconds
 	defaultKvstorehost          = "127.0.0.1"
 	defaultKvstoreport          = 2379 // Consul = 8500; Etcd = 2379
-	defaultLoglevel             = 0
+	defaultLoglevel             = "DEBUG"
 	defaultBanner               = false
 	defaultDisplayVersionOnly   = false
 	defaultTopic                = "openolt"
@@ -71,7 +71,7 @@
 	Topic                       string
 	CoreTopic                   string
 	EventTopic                  string
-	LogLevel                    int
+	LogLevel                    string
 	OnuNumber                   int
 	Banner                      bool
 	DisplayVersionOnly          bool
@@ -155,7 +155,7 @@
 	flag.IntVar(&(so.KVStorePort), "kv_store_port", defaultKvstoreport, help)
 
 	help = fmt.Sprintf("Log level")
-	flag.IntVar(&(so.LogLevel), "log_level", defaultLoglevel, help)
+	flag.StringVar(&(so.LogLevel), "log_level", defaultLoglevel, help)
 
 	help = fmt.Sprintf("Number of ONUs")
 	flag.IntVar(&(so.OnuNumber), "onu_number", defaultOnunumber, help)
diff --git a/main.go b/main.go
index 9a3b97a..6b07362 100644
--- a/main.go
+++ b/main.go
@@ -444,8 +444,10 @@
 
 	// Setup logging
 
+	loglevel := log.StringToInt(cf.LogLevel)
+
 	// Setup default logger - applies for packages that do not have specific logger set
-	if _, err := log.SetDefaultLogger(log.JSON, cf.LogLevel, log.Fields{"instanceId": cf.InstanceID}); err != nil {
+	if _, err := log.SetDefaultLogger(log.JSON, loglevel, log.Fields{"instanceId": cf.InstanceID}); err != nil {
 		log.With(log.Fields{"error": err}).Fatal("Cannot setup logging")
 	}