[VOL-1862] rwCore waits for kafka and KV Store

This commit is a cherry pick into the master branch from the
voltha 2.1 branch of patch https://gerrit.opencord.org/#/c/15030/

Change-Id: I8a306c8b37ad700ef8234466919e0604e14787cd
diff --git a/db/kvstore/consulclient.go b/db/kvstore/consulclient.go
index 4b25b5f..c4fa0af 100644
--- a/db/kvstore/consulclient.go
+++ b/db/kvstore/consulclient.go
@@ -63,6 +63,12 @@
 	return &ConsulClient{consul: consul, doneCh: &doneCh, watchedChannelsContext: wChannelsContext, keyReservations: reservations}, nil
 }
 
+// IsConnectionUp returns whether the connection to the Consul KV store is up
+func (c *ConsulClient) IsConnectionUp(timeout int) bool {
+	log.Error("Unimplemented function")
+	return false
+}
+
 // 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 *ConsulClient) List(key string, timeout int, lock ...bool) (map[string]*KVPair, error) {