This patch adds support for an optional reset pin.

The reset pin is used to bring the chip into a known state and has an
internal pull-down, allowing it to be left floating if not needed.
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230714081902.2621771-1-Naresh.Solanki@9elements.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>