Add code simplifications for staticheck

[hakman]

Ref: #7800

This change adds back code simplification checks.
It also makes the style rules we are breaking explicit, to prevent other types of style checks to break and to make it easier to fix style these later if wanted.

Errors from staticcheck:
cmd/kops/toolbox_template.go:138:38: should use make(map[string]string) instead (S1019)
cmd/kops/toolbox_template.go:215:42: should use make(map[string]interface{}) instead (S1019)
cmd/kops/toolbox_template.go:228:40: should use make(map[string]interface{}) instead (S1019)
dns-controller/pkg/watchers/ingress.go:170:4: should merge variable declaration with assignment on next line (S1021)
dns-controller/pkg/watchers/service.go:206:5: should merge variable declaration with assignment on next line (S1021)
upup/pkg/fi/cloudup/alitasks/vpc.go:64:5: should omit nil check; len() for nil slices is defined as zero (S1009)
upup/pkg/fi/cloudup/openstacktasks/volume.go:73:2: unnecessary guard around call to delete (S1033)
upup/pkg/fi/cloudup/openstacktasks/volume.go:76:2: unnecessary guard around call to delete (S1033)

[k8s-ci-robot]

Hi @hakman. Thanks for your PR.

I'm waiting for a kubernetes member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[hakman]

/cc @rifelpet
/cc @tanjunchen

[rifelpet]

/ok-to-test

Nice work on enumerating the ignored checks! I also noticed that more recent versions of staticcheck have additional checks that kops fails, so it might be worth upgrading our vendored version at some point too.

[hakman]

That would be nice. We should give it a try once the ignored failures list is gone.

[hakman]

/test pull-kops-e2e-kubernetes-aws

[tanjunchen]

it seems that you repeat with me , but you first . i will rebase . hehe

[tanjunchen]

good job!

[hakman]

/test pull-kops-e2e-kubernetes-aws

[hakman]

/test pull-kops-e2e-kubernetes-aws

[rifelpet]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hakman, rifelpet

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