amba: tegra-ahb: Fix warning w/o PM_SLEEP

Fix build warning w/o PM_SLEEP.
Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>

drivers/amba/tegra-ahb.c

@@ -156,6 +156,7 @@ int tegra_ahb_enable_smmu(struct device_node *dn)
 EXPORT_SYMBOL(tegra_ahb_enable_smmu);
 #endif
 
+#ifdef CONFIG_PM_SLEEP
 static int tegra_ahb_suspend(struct device *dev)
 {
 	int i;
@@ -175,6 +176,7 @@ static int tegra_ahb_resume(struct device *dev)
 		gizmo_writel(ahb, ahb->ctx[i], tegra_ahb_gizmo[i]);
 	return 0;
 }
+#endif
 
 static UNIVERSAL_DEV_PM_OPS(tegra_ahb_pm,
 			    tegra_ahb_suspend,