dt-bindings: reset: document deprecated HiSilicon property

Documenting deprecated property prevents dt-schema validation errors.

Signed-off-by: David Heidelberg <david@ixit.cz>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211208184149.99537-1-david@ixit.cz


Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>