VOL-1900 lint warning fixes rw_core

Change-Id: Icaa84d7ce24163da90c91ff2babcbb78ff4e9141
diff --git a/rw_core/coreif/core_if.go b/rw_core/coreif/core_if.go
new file mode 100644
index 0000000..c63a738
--- /dev/null
+++ b/rw_core/coreif/core_if.go
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/*
+Defines a DeviceManager Interface - Used for unit testing of the flow decomposer only at this
+time.
+*/
+
+package coreif
+
+import (
+	"context"
+
+	"github.com/opencord/voltha-go/db/model"
+	"github.com/opencord/voltha-go/rw_core/config"
+	"github.com/opencord/voltha-lib-go/v2/pkg/kafka"
+)
+
+// Core represent core methods
+type Core interface {
+	Start(ctx context.Context)
+	Stop(ctx context.Context)
+	GetKafkaInterContainerProxy() *kafka.InterContainerProxy
+	GetConfig() *config.RWCoreFlags
+	GetInstanceId() string
+	GetClusterDataProxy() *model.Proxy
+	GetAdapterManager() AdapterManager
+	StartGRPCService(ctx context.Context)
+	GetDeviceManager() DeviceManager
+	GetLogicalDeviceManager() LogicalDeviceManager
+	GetDeviceOwnerShip() DeviceOwnership
+}