ws: cockpit.socket should be able to listen on reserved ports

Update the SELinux policy.

This is the AVC that otherwise results:

```
type=AVC msg=audit(1400833955.781:264): avc:  denied  { name_bind } for  pid=1 comm="systemd" src=1001 scontext=system_u:system_r:cockpit_ws_t:s0 tcontext=system_u:object_r:hi_reserved_port_t:s0 tclass=tcp_socket
```