What happened:
Running make generate doesn't delete the generated files in pkg/client, and doesn't regenerate if they exist.

What you expected to happen:
Running make generate should delete any files it cannot overwrite.

How to reproduce it (as minimally and precisely as possible):
make generate
change or add a CRD
make generate
/hack/../hack/verify-golint.sh
some files are not regenerated and errors are seen in the linter output

Anything else we need to know?:
Files starting with zz_generated are overwritten, they don't need to be cleaned up.