PM / wakeup: wakeup_source_create: use kstrdup_const

Using kstrdup_const allows us to save a little runtime memory (and a
string copy) in the common case where name is a string literal.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/base/power/wakeup.c

@@ -94,7 +94,7 @@ struct wakeup_source *wakeup_source_create(const char *name)
 	if (!ws)
 		return NULL;
 
-	wakeup_source_prepare(ws, name ? kstrdup(name, GFP_KERNEL) : NULL);
+	wakeup_source_prepare(ws, name ? kstrdup_const(name, GFP_KERNEL) : NULL);
 	return ws;
 }
 EXPORT_SYMBOL_GPL(wakeup_source_create);
@@ -157,7 +157,7 @@ void wakeup_source_destroy(struct wakeup_source *ws)
 
 	wakeup_source_drop(ws);
 	wakeup_source_record(ws);
-	kfree(ws->name);
+	kfree_const(ws->name);
 	kfree(ws);
 }
 EXPORT_SYMBOL_GPL(wakeup_source_destroy);