Add support for azure autodiscovery with autoscaler helm chart.

[nclaeys]

Which component this PR applies to?

helm chart of the cluster-autoscaler

What type of PR is this?

/kind feature

What this PR does / why we need it:

The cluster auto-scaler for Azure supports auto-discovery but the helm chart does not. Added basic support for discovering node groups when using Azure.

Which issue(s) this PR fixes:

/

Special notes for your reviewer:

/

Does this PR introduce a user-facing change?

Added support to auto discover node groups to the helm chart when using the  Azure cloudProvider.

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: nclaeys / name: Niels Claeys (c10f05f)

[k8s-ci-robot]

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[mwielgus]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: mwielgus, nclaeys

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