VOL-4274 Move platform.go file to voltha-lib-go
This file exists both in olt-adapter and onu-adapter with duplicate constants and functions.
Becaues it includes constants and functions that can be used by any VOLTHA component,
it is more convenient to move it to voltha-lib. Adapters will be changed after lib is merged.

Change-Id: Idd51947d7efcfd28ebaa2e6e1da07a79e3091f45
diff --git a/pkg/platform/common.go b/pkg/platform/common.go
new file mode 100644
index 0000000..dbef567
--- /dev/null
+++ b/pkg/platform/common.go
@@ -0,0 +1,31 @@
+/*
+ * Copyright 2020-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 platform
+
+import (
+	"github.com/opencord/voltha-lib-go/v7/pkg/log"
+)
+
+var logger log.CLogger
+
+func init() {
+	// Setup this package so that it's log level can be modified at run time
+	var err error
+	logger, err = log.RegisterPackage(log.JSON, log.ErrorLevel, log.Fields{})
+	if err != nil {
+		panic(err)
+	}
+}