changelog v2.2.1

[pohly]

What type of PR is this?
/kind documentation

What this PR does / why we need it:

Last step before a v2.2.1 release.

Special notes for your reviewer:

Merging #624 would be useful, but isn't required.

Does this PR introduce a user-facing change?:

NONE

[k8s-ci-robot]

@pohly: The following test failed, say /retest to rerun all failed tests:

Test name	Commit	Details	Rerun command
pull-kubernetes-csi-external-provisioner-1-21-on-kubernetes-1-21	2de78b9	link	/test pull-kubernetes-csi-external-provisioner-1-21-on-kubernetes-1-21

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

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[chrishenzie]

LGTM other than test failure

/lgtm

[pohly]

LGTM other than test failure

Test failures in "1-21-on-kubernetes-1-21" can be ignored. We need to first release csi-driver-host-path, then update all repos to use that release for testing.

[msau42]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: msau42, pohly

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