pinctrl: ocelot: add MSCC Jaguar2 support

Jaguar2 has the same register layout as Ocelot but it has 64 pins, meaning
that there are 2 registers instead of one.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>