Fix machine deployment controller revision annotation update

[alvaroaleman]

What this PR does / why we need it:

Currently the machineDeployment controller updates the machineDeployment status instead of the machineDeployment itself after the DeploymentRevision got changed

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

Special notes for your reviewer:

Release note:

NONE

[xmudrii]

/ok-to-test

[alvaroaleman]

/assign @timothysc

[timothysc]

/assign @kris-nova @roberthbailey
/unassign @timothysc

[alvaroaleman]

SetDeploymentRevision one line above this comment where I can unfortunatelly not comment updates an annotation if required:

cluster-api/pkg/controller/machinedeployment/util/util.go

Line 115 in 3d9767c

func SetDeploymentRevision(deployment *v1alpha1.MachineDeployment, revision string) bool {

Consequently we must update the MachienDeployment, not its status.

The current behaviour results in the UpdateStatus being basically a no-op, except it triggers the informer, which then triggers the sync, which triggers this UpdateStatus again etc.

[roberthbailey]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: alvaroaleman, roberthbailey

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