(maint) fix cisco-9k/cisco-n9k typo
(maint) fix cisco-9k/cisco-n9k typo

```
david@davids:~/git/beaker-hostgenerator$ curl -H "X-AUTH-TOKEN: $(vmpooler_token)" -s -X GET --url https://nspooler-service-prod-1.delivery.puppetlabs.net/api/v1/status/ | jq . | grep cisco-n9k
  "cisco-n9k-x86_64": {
david@davids:~/git/beaker-hostgenerator$
```

puppetlabs/beaker-hostgenerator