pinctrl: s32cc: initialize gpio_pin_config::list after kmalloc()

pinctrl: s32cc: initialize gpio_pin_config::list after kmalloc()

s32_pmx_gpio_request_enable() does not initialize the newly-allocated
gpio_pin_config::list before adding it to s32_pinctrl::gpio_configs.
This could result in a linked list corruption.

Initialize the new list_head with INIT_LIST_HEAD() to fix this.

Fixes: fd84aaa8173d ("pinctrl: add NXP S32 SoC family support")
Signed-off-by: Jared Kangas <jkangas@redhat.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>