[Feature] - Allow for disabling load balancer creation

[georgyo]

Is your feature request related to a problem? Please describe.

There are many scenarios when you might not want the Vultr CCM to create a loadbalancer. Even if you have a different k8s load balancing solution, the CCM will create a vultr loadbalancer in addition to the one you actually want.

An example use case is that Vultr has fantastic BGP support, and you may want to use metallb instead of a third party node balancer. In this case, you likely still want to have the other features of the CCM such as putting the node into the proper state for pod scheduling.

Describe the solution you'd like

A way to turn off load balancer creation. Either with an opt-out or opt-in service annotation, or even a global flag that can be set on the cluster.

Describe alternatives you've considered

The alternative is to just not run the CCM, which works okay, but isn't the ideal scenario.