Allow IOPS config option for io1 volumeType

[vgunapati]

Is this a BUG REPORT or FEATURE REQUEST?:
FEATURE
What happened:
Allow IOPS config option for io1 volumeType

instance-manager/api/v1alpha1/instancegroup_types.go

Lines 193 to 196 in 5843c10

	type NodeVolume struct {
	Name string `json:"name,omitempty"`
	Type string `json:"type,omitempty"`
	Size int64 `json:"size,omitempty"`

More Details about io1
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-volume-types.html

What you expected to happen:

How to reproduce it (as minimally and precisely as possible):

Anything else we need to know?:

Environment:

• Kubernetes version:

kubectl version -o yaml

Other debugging information (if applicable):

• InstanceGroup status:

kubectl describe instancegroup <ig-name>

• controller logs:

kubectl logs <instance-manager pod>

[eytan-avisror]

@vgunapati this should work if you set volume type to io1 in the instance group spec.

[eytan-avisror]

We should add all options from:
https://github.com/aws/aws-sdk-go/blob/v1.33.16/service/autoscaling/api.go#L9676-L9743