pm: make compile dummy when PM not enabled.

Signed-off-by: buxiasen <buxiasen@xiaomi.com>
diff --git a/include/nuttx/power/pm.h b/include/nuttx/power/pm.h
index 54d6f16..8b9a3f2 100644
--- a/include/nuttx/power/pm.h
+++ b/include/nuttx/power/pm.h
@@ -837,7 +837,9 @@
 #  define PM_WAKELOCK_DECLARE(v,n,d,s)
 #  define PM_WAKELOCK_DECLARE_STATIC(v,n,d,s)
 #  define pm_initialize()
+#  define pm_domain_register(domain,cb)       (0)
 #  define pm_register(cb)                     (0)
+#  define pm_domain_unregister(domain,cb)     (0)
 #  define pm_unregister(cb)                   (0)
 #  define pm_activity(domain,prio)
 #  define pm_stay(domain,state)