pinctrl: nomadik: Dereference gpio_chip properly

The irq data passed to irc_chip handlers i the struct gpio_chip
and nothing else. We are just lucky that the nomadik chip
pointer is first in the struct. Use the proper dereferencing
and helpers.

Reported-by: Marc Zyngier <maz@kernel.org>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220917203036.167607-1-linus.walleij@linaro.org


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