include VTS packaging task files

Change-Id: I8737412bf4e7b5c2db32325105e7c588949b959d
diff --git a/core/Makefile b/core/Makefile
index 033c79d..bf1bf03 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -2395,6 +2395,7 @@
 -include $(sort $(wildcard product/*/*/build/tasks/*.mk))
 # Also add test specifc tasks
 include $(sort $(wildcard platform_testing/build/tasks/*.mk))
+include $(sort $(wildcard test/vts/tools/build/tasks/*.mk))
 endif
 
 include $(BUILD_SYSTEM)/product-graph.mk