VOL-4077: Improve storage usage on etcd
- the onu adapter will now receive the tp instance on the
  inter-container kafka message and need not reach the etcd store
  to fetch it.
- on reconcile, the onu adapter need to go to the kv store to
  fetch the tp instance, but request the tp instance via a new
  API towards openolt adapter which in-turn will fetch from the
  cache.
- re-org the code in onu-metrics-manager to restore pm-data
  on reconcile to avoid panics by accessing uninitialzed data
  if ani-fsm were to try adding gem port for monitoring
  before pm-data is initialized properly.

Change-Id: I82a6de2772155f6e08390b671fe26d692dd02c99
diff --git a/vendor/github.com/opencord/voltha-lib-go/v5/pkg/adapters/adapterif/adapter_proxy_if.go b/vendor/github.com/opencord/voltha-lib-go/v5/pkg/adapters/adapterif/adapter_proxy_if.go
new file mode 100644
index 0000000..c514d6d
--- /dev/null
+++ b/vendor/github.com/opencord/voltha-lib-go/v5/pkg/adapters/adapterif/adapter_proxy_if.go
@@ -0,0 +1,45 @@
+/*
+ * 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.
+ */
+
+package adapterif
+
+import (
+	"context"
+
+	"github.com/golang/protobuf/proto"
+	ic "github.com/opencord/voltha-protos/v4/go/inter_container"
+)
+
+// AdapterProxy interface for AdapterProxy implementation.
+type AdapterProxy interface {
+	SendInterAdapterMessage(ctx context.Context,
+		msg proto.Message,
+		msgType ic.InterAdapterMessageType_Types,
+		fromAdapter string,
+		toAdapter string,
+		toDeviceID string,
+		proxyDeviceID string,
+		messageID string) error
+	TechProfileInstanceRequest(ctx context.Context,
+		tpPath string,
+		ponIntfID uint32,
+		onuID uint32,
+		uniID uint32,
+		fromAdapter string,
+		toAdapter string,
+		toDeviceID string,
+		proxyDeviceID string) (*ic.InterAdapterTechProfileDownloadMessage, error)
+}