Input: e3x0-button - switch to DEFINE_SIMPLE_DEV_PM_OPS() and pm_sleep_ptr()

SIMPLE_DEV_PM_OPS() is deprecated as it requires explicit protection
against unused function warnings. The new combination of pm_sleep_ptr()
and DEFINE_SIMPLE_DEV_PM_OPS() allows the compiler to see the functions,
thus suppressing the warning, but still allowing the unused code to be
removed. Thus also drop the __maybe_unused markings.

Signed-off-by: Jonathan Cameron <[e-mail]>
Cc: Moritz Fischer <[e-mail]>
Reviewed-by: Linus Walleij <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Dmitry Torokhov <[e-mail]>

drivers/input/misc/e3x0-button.c

···
 	return IRQ_HANDLED;
 }
 
-static int __maybe_unused e3x0_button_suspend(struct device *dev)
+static int e3x0_button_suspend(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 
···
 	return 0;
 }
 
-static int __maybe_unused e3x0_button_resume(struct device *dev)
+static int e3x0_button_resume(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 
···
 	return 0;
 }
 
-static SIMPLE_DEV_PM_OPS(e3x0_button_pm_ops,
-			 e3x0_button_suspend, e3x0_button_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(e3x0_button_pm_ops,
+				e3x0_button_suspend, e3x0_button_resume);
 
 static int e3x0_button_probe(struct platform_device *pdev)
 {
···
 	.driver		= {
 		.name	= "e3x0-button",
 		.of_match_table = of_match_ptr(e3x0_button_match),
-		.pm	= &e3x0_button_pm_ops,
+		.pm	= pm_sleep_ptr(&e3x0_button_pm_ops),
 	},
 	.probe		= e3x0_button_probe,
 };