No functional changes.

Adjust to comply with dt-schema requirements
and make possible to validate values.
Acked-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: David Heidelberg <david@ixit.cz>
Link: https://lore.kernel.org/r/20231209171653.85468-2-david@ixit.czSigned-off-by: Heiko Stuebner <heiko@sntech.de>