platform / x86 / PM: Fix unused function warnings for CONFIG_PM_SLEEP

According to compiler warnings, quite some suspend/resume functions
in platform x86 drivers are not used for CONFIG_PM_SLEEP unset, so
add #ifdefs to prevent them from being built in that case.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
diff --git a/drivers/platform/x86/panasonic-laptop.c b/drivers/platform/x86/panasonic-laptop.c
index 2448007..8e8caa7 100644
--- a/drivers/platform/x86/panasonic-laptop.c
+++ b/drivers/platform/x86/panasonic-laptop.c
@@ -188,7 +188,9 @@
 };
 MODULE_DEVICE_TABLE(acpi, pcc_device_ids);
 
+#ifdef CONFIG_PM_SLEEP
 static int acpi_pcc_hotkey_resume(struct device *dev);
+#endif
 static SIMPLE_DEV_PM_OPS(acpi_pcc_hotkey_pm, NULL, acpi_pcc_hotkey_resume);
 
 static struct acpi_driver acpi_pcc_driver = {
@@ -540,6 +542,7 @@
 
 /* kernel module interface */
 
+#ifdef CONFIG_PM_SLEEP
 static int acpi_pcc_hotkey_resume(struct device *dev)
 {
 	struct pcc_acpi *pcc;
@@ -556,6 +559,7 @@
 
 	return acpi_pcc_write_sset(pcc, SINF_STICKY_KEY, pcc->sticky_mode);
 }
+#endif
 
 static int acpi_pcc_hotkey_add(struct acpi_device *device)
 {