Fix lightwave config validation

[amelchio]

Breaking Change:

Lightwave configuration was not properly validated before, it is now. This can cause invalid configurations to finally be flagged as such.

Description:

A missing vol.All meant that the schema would validate anything as long as cv.has_at_least_one_key passed.

I do not use this component so I only tested startup.

Example entry for configuration.yaml (if applicable):

lightwave:
    lights:

Checklist:

• The code change is tested and works locally.
• Local tests pass with tox.
• There is no commented out code in this PR.

[andrewsayre]

Note to self... don't use GitHawk to try and add a label. It nukes them all...