remove not used variables

builder/ncloud/step_create_server_image.go

@@ -44,7 +44,7 @@ func (s *StepCreateServerImage) createServerImage(serverInstanceNo string) (*ncl
 
 	memberServerImageList, err := s.Conn.CreateMemberServerImage(reqParams)
 	if err != nil {
-		return nil, fmt.Errorf("error code: %d , error message: %s", memberServerImageList.ReturnCode, memberServerImageList.ReturnMessage)
+		return nil, err
 	}
 
 	serverImage := memberServerImageList.MemberServerImageList[0]

builder/ncloud/step_create_server_instance.go

@@ -55,7 +55,7 @@ func (s *StepCreateServerInstance) createServerInstance(loginKeyName string, zon
 
 	serverInstanceList, err := s.Conn.CreateServerInstances(reqParams)
 	if err != nil {
-		return "", fmt.Errorf("error code: %d, error message: %s", serverInstanceList.ReturnCode, serverInstanceList.ReturnMessage)
+		return "", err
 	}
 
 	s.serverInstanceNo = serverInstanceList.ServerInstanceList[0].ServerInstanceNo

builder/ncloud/step_delete_block_storage_instance.go

@@ -63,7 +63,7 @@ func (s *StepDeleteBlockStorageInstance) deleteBlockStorageInstance(serverInstan
 		return nil
 	}
 
-	result, err := s.Conn.DeleteBlockStorageInstances(blockStorageInstanceList)
+	_, err := s.Conn.DeleteBlockStorageInstances(blockStorageInstanceList)
 	if err != nil {
 		return err
 	}

builder/ncloud/step_delete_login_key.go

@@ -28,7 +28,7 @@ func NewStepDeleteLoginKey(conn *ncloud.Conn, ui packer.Ui) *StepDeleteLoginKey
 }
 
 func (s *StepDeleteLoginKey) deleteLoginKey(keyName string) error {
-	resp, err := s.Conn.DeleteLoginKey(keyName)
+	_, err := s.Conn.DeleteLoginKey(keyName)
 	if err != nil {
 		return err
 	}

builder/ncloud/step_get_rootpassword.go

@@ -1,8 +1,6 @@
 package ncloud
 
 import (
-	"fmt"
-
 	ncloud "github.com/NaverCloudPlatform/ncloud-sdk-go/sdk"
 	"github.com/hashicorp/packer/packer"
 	"github.com/mitchellh/multistep"

builder/ncloud/step_terminate_server_instance.go

@@ -2,7 +2,6 @@ package ncloud
 
 import (
 	"errors"
-	"fmt"
 	"time"
 
 	ncloud "github.com/NaverCloudPlatform/ncloud-sdk-go/sdk"
@@ -33,7 +32,7 @@ func (s *StepTerminateServerInstance) terminateServerInstance(serverInstanceNo s
 	reqParams := new(ncloud.RequestTerminateServerInstances)
 	reqParams.ServerInstanceNoList = []string{serverInstanceNo}
 
-	serverInstanceList, err := s.Conn.TerminateServerInstances(reqParams)
+	_, err := s.Conn.TerminateServerInstances(reqParams)
 	if err != nil {
 		return err
 	}