PM / Sleep: Add "prevent autosleep time" statistics to wakeup sources

Android uses one wakelock statistics that is only necessary for
opportunistic sleep.  Namely, the prevent_suspend_time field
accumulates the total time the given wakelock has been locked
while "automatic suspend" was enabled.  Add an analogous field,
prevent_sleep_time, to wakeup sources and make it behave in a similar
way.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/kernel/power/autosleep.c b/kernel/power/autosleep.c
index 42348e3..ca304046 100644
--- a/kernel/power/autosleep.c
+++ b/kernel/power/autosleep.c
@@ -101,8 +101,12 @@
 
 	__pm_relax(autosleep_ws);
 
-	if (state > PM_SUSPEND_ON)
+	if (state > PM_SUSPEND_ON) {
+		pm_wakep_autosleep_enabled(true);
 		queue_up_suspend_work();
+	} else {
+		pm_wakep_autosleep_enabled(false);
+	}
 
 	mutex_unlock(&autosleep_lock);
 	return 0;