PM / Domains: Fix build for CONFIG_PM_SLEEP unset

Some callback functions defined in drivers/base/power/domain.c are
only necessary if CONFIG_PM_SLEEP is set and they call some other
functions that are only available in that case.  For this reason,
they should not be compiled at all when CONFIG_PM_SLEEP is not set.

Reported-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 92e6a90..978bbf7 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -1429,6 +1429,8 @@
 	return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+
 /**
  * pm_genpd_default_suspend - Default "device suspend" for PM domians.
  * @dev: Device to handle.
@@ -1517,6 +1519,19 @@
 	return cb ? cb(dev) : pm_generic_thaw(dev);
 }
 
+#else /* !CONFIG_PM_SLEEP */
+
+#define pm_genpd_default_suspend	NULL
+#define pm_genpd_default_suspend_late	NULL
+#define pm_genpd_default_resume_early	NULL
+#define pm_genpd_default_resume		NULL
+#define pm_genpd_default_freeze		NULL
+#define pm_genpd_default_freeze_late	NULL
+#define pm_genpd_default_thaw_early	NULL
+#define pm_genpd_default_thaw		NULL
+
+#endif /* !CONFIG_PM_SLEEP */
+
 /**
  * pm_genpd_init - Initialize a generic I/O PM domain object.
  * @genpd: PM domain object to initialize.