[VOL-1754] :changes to handle device states on olt disable/re-enable

Change-Id: Iafcebc16cb739e7d17d8e42a4c4dbe66027dc27d
diff --git a/rw_core/core/device_agent.go b/rw_core/core/device_agent.go
index 103f37f..5b6a7f9 100755
--- a/rw_core/core/device_agent.go
+++ b/rw_core/core/device_agent.go
@@ -18,6 +18,10 @@
 import (
 	"context"
 	"fmt"
+	"reflect"
+	"sync"
+	"time"
+
 	"github.com/gogo/protobuf/proto"
 	coreutils "github.com/opencord/voltha-go/rw_core/utils"
 	"github.com/opencord/voltha-lib-go/v2/pkg/db/model"
@@ -28,9 +32,6 @@
 	"github.com/opencord/voltha-protos/v2/go/voltha"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
-	"reflect"
-	"sync"
-	"time"
 )
 
 type DeviceAgent struct {