Add permission check in notifyWakingUp/GoingToSleep

These AIDL were not protected by any permission.

Although there is no security risk associated with that, those two
methods are not intended to be public.

Bug: 280419125
Test: atest WallpaperManagerTest
Change-Id: Ia5a22fb2926a533b1aaaaa2cf0f49b46783d07c6