gpio: pch: Use modern PM macros

Use the modern PM macros for the suspend and resume functions to be
automatically dropped by the compiler when CONFIG_PM or
CONFIG_PM_SLEEP are disabled, without having to use __maybe_unused

Signed-off-by: Jisheng Zhang <[e-mail]>
Acked-by: Andy Shevchenko <[e-mail]>
Acked-by: Linus Walleij <[e-mail]>
Reviewed-by: Andy Shevchenko <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Bartosz Golaszewski <[e-mail]>

drivers/gpio/gpio-pch.c

···
 /*
  * Save register configuration and disable interrupts.
  */
-static void __maybe_unused pch_gpio_save_reg_conf(struct pch_gpio *chip)
+static void pch_gpio_save_reg_conf(struct pch_gpio *chip)
 {
 	chip->pch_gpio_reg.ien_reg = ioread32(&chip->reg->ien);
 	chip->pch_gpio_reg.imask_reg = ioread32(&chip->reg->imask);
···
 /*
  * This function restores the register configuration of the GPIO device.
  */
-static void __maybe_unused pch_gpio_restore_reg_conf(struct pch_gpio *chip)
+static void pch_gpio_restore_reg_conf(struct pch_gpio *chip)
 {
 	iowrite32(chip->pch_gpio_reg.ien_reg, &chip->reg->ien);
 	iowrite32(chip->pch_gpio_reg.imask_reg, &chip->reg->imask);
···
 	return pch_gpio_alloc_generic_chip(chip, irq_base, gpio_pins[chip->ioh]);
 }
 
-static int __maybe_unused pch_gpio_suspend(struct device *dev)
+static int pch_gpio_suspend(struct device *dev)
 {
 	struct pch_gpio *chip = dev_get_drvdata(dev);
 	unsigned long flags;
···
 	return 0;
 }
 
-static int __maybe_unused pch_gpio_resume(struct device *dev)
+static int pch_gpio_resume(struct device *dev)
 {
 	struct pch_gpio *chip = dev_get_drvdata(dev);
 	unsigned long flags;
···
 	return 0;
 }
 
-static SIMPLE_DEV_PM_OPS(pch_gpio_pm_ops, pch_gpio_suspend, pch_gpio_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(pch_gpio_pm_ops, pch_gpio_suspend, pch_gpio_resume);
 
 static const struct pci_device_id pch_gpio_pcidev_id[] = {
 	{ PCI_DEVICE_DATA(INTEL, EG20T_PCH, INTEL_EG20T_PCH) },
···
 	.id_table = pch_gpio_pcidev_id,
 	.probe = pch_gpio_probe,
 	.driver = {
-		.pm = &pch_gpio_pm_ops,
+		.pm = pm_sleep_ptr(&pch_gpio_pm_ops),
 	},
 };