[VOL-1645] Fix for device agents creation

Change-Id: I1a17bd689e458088b42963d395abf6b96180f5b8
diff --git a/rw_core/core/device_agent.go b/rw_core/core/device_agent.go
index e7089cd..4e31ff8 100755
--- a/rw_core/core/device_agent.go
+++ b/rw_core/core/device_agent.go
@@ -33,6 +33,7 @@
 
 type DeviceAgent struct {
 	deviceId         string
+	parentId         string
 	deviceType       string
 	isRootdevice     bool
 	lastData         *voltha.Device
@@ -65,6 +66,7 @@
 	}
 	agent.isRootdevice = device.Root
 	agent.deviceId = cloned.Id
+	agent.parentId = device.ParentId
 	agent.deviceType = cloned.Type
 	agent.lastData = cloned
 	agent.deviceMgr = deviceMgr