CONFIG_PM will be set if either or both CONFIG_PM_SLEEP and
CONFIG_PM_RUNTIME is set. Compiling the driver with !CONFIG_PM_SLEEP causes
following compilation warnings:
drivers/tty/serial/8250/8250_dw.c:404:12: warning: ‘dw8250_suspend’ defined but not used [-Wunused-function]
drivers/tty/serial/8250/8250_dw.c:413:12: warning: ‘dw8250_resume’ defined but not used [-Wunused-function]
Fix this by using CONFIG_PM_SLEEP instead.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
        return 0;
 }
 
-#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
 static int dw8250_suspend(struct device *dev)
 {
        struct dw8250_data *data = dev_get_drvdata(dev);
 
        return 0;
 }
-#endif /* CONFIG_PM */
+#endif /* CONFIG_PM_SLEEP */
 
 #ifdef CONFIG_PM_RUNTIME
 static int dw8250_runtime_suspend(struct device *dev)