This fixes the issue where book GUIs are lit inconsistently

[cherry picked from H'uru commit 23127c95a178467022173360bb9cd884fda9ebfe]

MOULOpenSourceClientPlugin/Plasma20/Sources/Plasma/PubUtilLib/plPipeline/plDXPipeline.cpp

@@ -982,6 +982,10 @@ void	plDXPipeline::IInitDeviceState()
 
 	fLights.Reset(this);
 
+	// Tell the light infos to unlink themselves
+	while (fActiveLights)
+		UnRegisterLight(fActiveLights);
+
 	return;
 }