dt-bindings: vendor-prefixes: document Novatek

Document Novatek vendor prefix already used for Novatek nt36672a panel.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230326155719.91780-1-krzysztof.kozlowski@linaro.org


Signed-off-by: Rob Herring <robh@kernel.org>