PM: device_suspend/resume may sleep

This adds warning when someone tries them from atomic context.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/base/power/resume.c

@@ -96,6 +96,7 @@ void dpm_resume(void)
 
 void device_resume(void)
 {
+	might_sleep();
 	down(&dpm_sem);
 	dpm_resume();
 	up(&dpm_sem);

drivers/base/power/suspend.c

@@ -140,6 +140,7 @@ int device_suspend(pm_message_t state)
 {
 	int error = 0;
 
+	might_sleep();
 	down(&dpm_sem);
 	down(&dpm_list_sem);
 	while (!list_empty(&dpm_active) && error == 0) {