VOL-2362 - add exponential backoff around enabling indications

Change-Id: I212312f297a0ca5ae33a4250bac1008e9be2f2c2
diff --git a/go.mod b/go.mod
index 92454eb..9d21cb0 100644
--- a/go.mod
+++ b/go.mod
@@ -3,6 +3,7 @@
 go 1.12
 
 require (
+	github.com/cenkalti/backoff/v3 v3.1.1
 	github.com/gogo/protobuf v1.3.1
 	github.com/golang/protobuf v1.3.2
 	github.com/opencord/voltha-lib-go/v2 v2.2.20