Pass the correct port so knife-opc works when non-defaults are used.

Ping @opscode/server-team 

Fixes issue https://github.com/opscode/opscode-omnibus/issues/498 by passing the port to the pivotal config. See there for description of issue.
If the answer to the above is no and we always wanna use ssl for the knife-opc wrapper, then simply do

```
port = node['private_chef']['nginx']['ssl_port']
```