hwmon: (ina3221) mark PM functions as __maybe_unused

When CONFIG_PM_SLEEP is disabled, we get a warning about unused
suspend/resume functions:

drivers/hwmon/ina3221.c:451:12: error: 'ina3221_resume' defined but not used [-Werror=unused-function]
 static int ina3221_resume(struct device *dev)
drivers/hwmon/ina3221.c:428:12: error: 'ina3221_suspend' defined but not used [-Werror=unused-function]
 static int ina3221_suspend(struct device *dev)

Picking the correct #ifdef check is hard, so let's remove
that check and instead mark the functions as __maybe_unused
to let the compiler silently drop them instead.

Fixes: 7de1ab9dac8e ("hwmon: (ina3221) Add suspend and resume functions")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/ina3221.c

@@ -631,8 +631,7 @@ static int ina3221_probe(struct i2c_client *client,
 	return 0;
 }
 
-#ifdef CONFIG_PM
-static int ina3221_suspend(struct device *dev)
+static int __maybe_unused ina3221_suspend(struct device *dev)
 {
 	struct ina3221_data *ina = dev_get_drvdata(dev);
 	int ret;
@@ -655,7 +654,7 @@ static int ina3221_suspend(struct device *dev)
 	return 0;
 }
 
-static int ina3221_resume(struct device *dev)
+static int __maybe_unused ina3221_resume(struct device *dev)
 {
 	struct ina3221_data *ina = dev_get_drvdata(dev);
 	int ret;
@@ -681,7 +680,6 @@ static int ina3221_resume(struct device *dev)
 
 	return 0;
 }
-#endif
 
 static const struct dev_pm_ops ina3221_pm = {
 	SET_SYSTEM_SLEEP_PM_OPS(ina3221_suspend, ina3221_resume)