VOL-3735 Retrieve port counters using the GetExtValue(SingleGetValue) rpc from the openolt adapter

Change-Id: Ie7cd02b6a5b3784d7cc279a616ce88d4ee89ef20
diff --git a/go.sum b/go.sum
index eb285da..f7e0eeb 100644
--- a/go.sum
+++ b/go.sum
@@ -196,8 +196,8 @@
 github.com/onsi/ginkgo v1.6.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
 github.com/onsi/gomega v1.4.2 h1:3mYCb7aPxS/RU7TI1y4rkEn1oKmPRjNJLNEXgw7MH2I=
 github.com/onsi/gomega v1.4.2/go.mod h1:ex+gbHU/CVuBBDIJjb2X0qEXbFg53c61hWP/1CpauHY=
-github.com/opencord/voltha-protos/v4 v4.0.6 h1:cR5QO9yMMIn2zEwTxcUwxDMfQ5Zh3jBqhprw4xhdyAU=
-github.com/opencord/voltha-protos/v4 v4.0.6/go.mod h1:W/OIFIyvFh/C0vchRUuarIsMylEhzCRM9pNxLvkPtKc=
+github.com/opencord/voltha-protos/v4 v4.0.8 h1:/P9IYuWPTp/aabS5n1fakQgHCFNzKjW1JHw3TOLAfKE=
+github.com/opencord/voltha-protos/v4 v4.0.8/go.mod h1:W/OIFIyvFh/C0vchRUuarIsMylEhzCRM9pNxLvkPtKc=
 github.com/opentracing/opentracing-go v1.1.0 h1:pWlfV3Bxv7k65HYwkikxat0+s3pV4bsqf19k25Ur8rU=
 github.com/opentracing/opentracing-go v1.1.0/go.mod h1:UkNAQd3GIcIGf0SeVgPpRdFStlNbqXla1AfSYxPUl2o=
 github.com/pascaldekloe/goe v0.0.0-20180627143212-57f6aae5913c/go.mod h1:lzWF7FIEvWOWxwDKqyGYQf6ZUaNfKdP144TG7ZOy1lc=