dmaengine: idma64: Switch to use __maybe_unused instead of ifdeffery

ifdeffery is prone to errors and makes code harder to read.
Switch to use __maybe_unused instead of ifdeffery.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20201104103131.89907-1-andriy.shevchenko@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/idma64.c

@@ -667,9 +667,7 @@ static int idma64_platform_remove(struct platform_device *pdev)
 	return idma64_remove(chip);
 }
 
-#ifdef CONFIG_PM_SLEEP
-
-static int idma64_pm_suspend(struct device *dev)
+static int __maybe_unused idma64_pm_suspend(struct device *dev)
 {
 	struct idma64_chip *chip = dev_get_drvdata(dev);
 
@@ -677,7 +675,7 @@ static int idma64_pm_suspend(struct device *dev)
 	return 0;
 }
 
-static int idma64_pm_resume(struct device *dev)
+static int __maybe_unused idma64_pm_resume(struct device *dev)
 {
 	struct idma64_chip *chip = dev_get_drvdata(dev);
 
@@ -685,8 +683,6 @@ static int idma64_pm_resume(struct device *dev)
 	return 0;
 }
 
-#endif /* CONFIG_PM_SLEEP */
-
 static const struct dev_pm_ops idma64_dev_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(idma64_pm_suspend, idma64_pm_resume)
 };