For HCP clusters, cluster autoscaler is created automatically with default values when the cluster is created. In machine pools tab, UI should allow user to - 

1. View the existing cluster autoscaler settings
2. Edit (and save) the cluster autscaler settings

Currently only 4 fields are supported -

1. MaxNodesTotal,
2. maxPodGracePeriod
3. maxNodeProvisionTime
4. podPriorityThreshold

Out of scope:

1. Day 1 (Configuring autscaler settings in ROSA HCP wizard is out of scope since the autoscaler is created automatically).
2. Deleting (/disabling) the cluster autscaler is not supported, this actions should not be presented to users.