/kind feature /area provider/eks **Describe the solution you'd like** Add support for configuring the [cluster authentication mode](https://docs.aws.amazon.com/eks/latest/userguide/access-entries.html#authentication-modes) to the AWSManagedControlPlane spec, and a controller to sync [AccessEntries](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-eks-accessentry.html) (either within the spec as iamAuthenticatorConfig mapRoles current are, or as a separate CRD).