iio:light:cm3232: Switch from CONFIG_PM_SLEEP guards to pm_sleep_ptr() etc

Letting the compiler remove these functions when the kernel is built
without CONFIG_PM_SLEEP support is simpler and less error prone than the
use of #ifdef based config guards.  Also switch to SIMPLE_DEV_PM_OPS rather
than opencoding the same.

Removing instances of this approach from IIO also stops them being
copied into new drivers.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20220130193147.279148-20-jic23@kernel.org

drivers/iio/light/cm3232.c

@@ -374,7 +374,6 @@ static const struct i2c_device_id cm3232_id[] = {
 	{}
 };
 
-#ifdef CONFIG_PM_SLEEP
 static int cm3232_suspend(struct device *dev)
 {
 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
@@ -403,9 +402,7 @@ static int cm3232_resume(struct device *dev)
 	return ret;
 }
 
-static const struct dev_pm_ops cm3232_pm_ops = {
-	SET_SYSTEM_SLEEP_PM_OPS(cm3232_suspend, cm3232_resume)};
-#endif
+static DEFINE_SIMPLE_DEV_PM_OPS(cm3232_pm_ops, cm3232_suspend, cm3232_resume);
 
 MODULE_DEVICE_TABLE(i2c, cm3232_id);
 
@@ -419,9 +416,7 @@ static struct i2c_driver cm3232_driver = {
 	.driver = {
 		.name	= "cm3232",
 		.of_match_table = cm3232_of_match,
-#ifdef CONFIG_PM_SLEEP
-		.pm	= &cm3232_pm_ops,
-#endif
+		.pm	= pm_sleep_ptr(&cm3232_pm_ops),
 	},
 	.id_table	= cm3232_id,
 	.probe		= cm3232_probe,