dt-bindings: pinctrl: ocelot: add reset property

On the LAN966x SoC the GPIO controller will be resetted together with
the SGPIO and the switch core. Add a phandle to register the shared
reset line.

Signed-off-by: Michael Walle <michael@walle.cc>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220420191926.3411830-2-michael@walle.cc


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>