PM: don't skip device PM init when CONFIG_PM_SLEEP isn't set and CONFIG_PM is set

This patch (as1124) fixes a couple of bugs in the PM core.  The new
dev->power.status field should be initialized regardless of whether
CONFIG_PM_SLEEP is enabled, and similarly dpm_sysfs_add() should be
called whenever CONFIG_PM is enabled.

The patch separates out the call to dpm_sysfs_add() from the call to
device_pm_add().  As a result device_pm_add() can no longer return an
error, so its return type is changed to void.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Romit Dasgupta <romit@ti.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h
index a3252c0..41f51fa 100644
--- a/drivers/base/power/power.h
+++ b/drivers/base/power/power.h
@@ -1,3 +1,8 @@
+static inline void device_pm_init(struct device *dev)
+{
+	dev->power.status = DPM_ON;
+}
+
 #ifdef CONFIG_PM_SLEEP
 
 /*
@@ -11,12 +16,12 @@
 	return container_of(entry, struct device, power.entry);
 }
 
-extern int device_pm_add(struct device *);
+extern void device_pm_add(struct device *);
 extern void device_pm_remove(struct device *);
 
 #else /* CONFIG_PM_SLEEP */
 
-static inline int device_pm_add(struct device *dev) { return 0; }
+static inline void device_pm_add(struct device *dev) {}
 static inline void device_pm_remove(struct device *dev) {}
 
 #endif