[#181] container: setup nns keys during update

Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>

container/container_contract.go

@@ -92,6 +92,8 @@ func _deploy(data interface{}, isUpdate bool) {
 	nnsRoot := args[5].(string)
 
 	if isUpdate {
+		storage.Put(ctx, nnsContractKey, addrNNS)
+		storage.Put(ctx, nnsRootKey, nnsRoot)
 		registerNiceNameTLD(addrNNS, nnsRoot)
 		return
 	}