VOL-1845 : Support for delete device in openolt adapter

           This commit is for the handling of delete device.

           The changes are done to handle the request for delete
           device. This includes the clearing of all data related
           to the device in KV store and reboot of device to reset
           the device.

           This commit has dependency in voltha-go so that needs to
           be merged first. Please refer this review link
           https://gerrit.opencord.org/#/c/15084/

           Updated to dep ensure above voltha-go patch set.  Also typo
           and make lint/sca fixes.

Change-Id: I53f16022c6902d498dad30e9b7d0ff50bf156347
diff --git a/vendor/github.com/opencord/voltha-go/db/kvstore/etcdclient.go b/vendor/github.com/opencord/voltha-go/db/kvstore/etcdclient.go
index 7f6940a..f19f365 100644
--- a/vendor/github.com/opencord/voltha-go/db/kvstore/etcdclient.go
+++ b/vendor/github.com/opencord/voltha-go/db/kvstore/etcdclient.go
@@ -59,6 +59,16 @@
 		lockToSessionMap: lockSessionMap}, nil
 }
 
+// IsConnectionUp returns whether the connection to the Etcd KV store is up.  If a timeout occurs then
+// it is assumed the connection is down or unreachable.
+func (c *EtcdClient) IsConnectionUp(timeout int) bool {
+	// Let's try to get a non existent key.  If the connection is up then there will be no error returned.
+	if _, err := c.Get("non-existent-key", timeout); err != nil {
+		return false
+	}
+	return true
+}
+
 // List returns an array of key-value pairs with key as a prefix.  Timeout defines how long the function will
 // wait for a response
 func (c *EtcdClient) List(key string, timeout int, lock ...bool) (map[string]*KVPair, error) {