Z-Wave: multi instance encap response handler fixed

This fixes response handler for multi-instance responses in case a command class is not supported as regular command.
I think this line should be 
```
if (endpoint != null && this.getVersion() >= 2) {
```
since individual command classes are only supported in version 2. It doesn't matter due to the fact you check the command classes in the node, but it's probably best to use it.