enable vts tests for light hal.

Test: run vts -m LightHidlTargetTest --abi arm64-v8a
Change-Id: I27a1a0d8fe9b7a807815bba9b32b107ebf87925d
diff --git a/light/2.0/vts/Android.mk b/light/2.0/vts/Android.mk
index 59e8f35..0df4772 100644
--- a/light/2.0/vts/Android.mk
+++ b/light/2.0/vts/Android.mk
@@ -45,3 +45,5 @@
 LOCAL_MULTILIB := both
 
 include $(BUILD_SHARED_LIBRARY)
+
+include $(call all-makefiles-under,$(LOCAL_PATH))