net: macb: Remove CONFIG_PM ifdef because of compilation warning

Fix compilation warning:
drivers/net/ethernet/cadence/macb.c:2415:12: warning: 'macb_suspend'
defined but not used [-Wunused-function]
 static int macb_suspend(struct device *dev)
drivers/net/ethernet/cadence/macb.c:2432:12: warning: 'macb_resume'
defined but not used [-Wunused-function]
 static int macb_resume(struct device *dev)

when CONFIG_PM=y, CONFIG_PM_SLEEP=n are used.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/cadence/macb.c

@@ -2469,8 +2469,7 @@ static int macb_remove(struct platform_device *pdev)
 	return 0;
 }
 
-#ifdef CONFIG_PM
-static int macb_suspend(struct device *dev)
+static int __maybe_unused macb_suspend(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct net_device *netdev = platform_get_drvdata(pdev);
@@ -2487,7 +2486,7 @@ static int macb_suspend(struct device *dev)
 	return 0;
 }
 
-static int macb_resume(struct device *dev)
+static int __maybe_unused macb_resume(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct net_device *netdev = platform_get_drvdata(pdev);
@@ -2502,7 +2501,6 @@ static int macb_resume(struct device *dev)
 
 	return 0;
 }
-#endif
 
 static SIMPLE_DEV_PM_OPS(macb_pm_ops, macb_suspend, macb_resume);