dt-bindings: vendor-prefixes: add MaxLinear

MaxLinear is a manufacturer of integrated circuits.
https://www.maxlinear.com



Signed-off-by: Michael Walle <michael@walle.cc>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>