Update hyper-v.md

[suse-coder]

Pull Request

What? (description)

Add that after it was created one needs to remove the media to none. Otherwise one can get during restart the type:none which can make newcomer think that talos would be instable or had installation problems.

Why? (reasoning)

Acceptance

Please use the following checklist:

• you linked an issue (if applicable)
• you included tests (if applicable)
• you ran conformance (make conformance)
• you formatted your code (make fmt)
• you linted your code (make lint)
• you generated documentation (make docs)
• you ran unit-tests (make unit-tests)

See make help for a description of the available targets.

[smira]

thank you!

[smira]

/m