Implement MetalLB LoadBalancer support

[jmkeyes]

What this PR does / why we need it:
The current implementation of bare metal deployment uses a NodePort type service to expose the ingress controller. This PR implements support for the LoadBalancer type service as an alternative that works well with an on-premise (L2) MetalLB deployment.

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[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: jmkeyes
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[aledbf]

@jmkeyes thank you for the PR but we prefer to keep it simple and let users customize the installation as they want. We cannot provide every available option in the docs.