pinctrl: use more common syntax for compound literals

The (typeof(foo)) construct is unusual in the kernel, use a more typical
syntax by explicitly spelling out the type.

Link: https://lore.kernel.org/all/20250909-gpio-mmio-gpio-conv-part4-v1-13-9f723dc3524a@linaro.org/


Suggested-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>