Added support for AWS inf2 instance types

[ff-apple]

What type of PR is this?

🍒 from master | reference PR #5529

/kind feature

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #5684

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

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

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[ff-apple]

Adding @gjtempleton here as already familiar with the change as was the reviewer of PR #5529

FYI: @mmcclean-aws

[ff-apple]

@feiskyer @Jeffwan can you please take a look? Thank you

[mwielgus]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: ff-apple, mwielgus

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