pinctrl: pinctrl-single: fix compile warning when no CONFIG_PM

This warning has been introduced by the commit
 0f9bc4bc pinctrl: single: adopt pinctrl sleep mode management
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/pinctrl-single.c

@@ -1483,6 +1483,7 @@ static int pcs_add_gpio_func(struct device_node *node, struct pcs_device *pcs)
 	return ret;
 }
 
+#ifdef CONFIG_PM
 static int pinctrl_single_suspend(struct platform_device *pdev,
 					pm_message_t state)
 {
@@ -1505,6 +1506,7 @@ static int pinctrl_single_resume(struct platform_device *pdev)
 
 	return pinctrl_force_default(pcs->pctl);
 }
+#endif
 
 static int pcs_probe(struct platform_device *pdev)
 {