Add build_verity_metadata.py to dist-tools

Preserve path as it is referenced by build_image.py.

Change-Id: Id6833d243b5a15b4ee5e0013340aeb2cd35f3578
diff --git a/core/Makefile b/core/Makefile
index 460994e..b227d0a 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -1288,9 +1288,10 @@
 $(BUILT_OTATOOLS_PACKAGE): $(OTATOOLS) | $(ACP)
 	@echo "Package OTA tools: $@"
 	$(hide) rm -rf $@ $(zip_root)
-	$(hide) mkdir -p $(dir $@) $(zip_root)/bin $(zip_root)/framework $(zip_root)/releasetools
+	$(hide) mkdir -p $(dir $@) $(zip_root)/bin $(zip_root)/framework $(zip_root)/releasetools $(zip_root)/system/extras/verity
 	$(call copy-files-with-structure,$(OTATOOLS),$(HOST_OUT)/,$(zip_root))
 	$(hide) $(ACP) $(HOST_OUT_JAVA_LIBRARIES)/VeritySigner.jar $(zip_root)/framework/
+	$(hide) $(ACP) -p system/extras/verity/build_verity_metadata.py $(zip_root)/system/extras/verity/
 	$(hide) $(ACP) -r -d -p build/tools/releasetools/* $(zip_root)/releasetools
 	$(hide) rm -rf $@ $(zip_root)/releasetools/*.pyc
 	$(hide) (cd $(zip_root) && zip -qry $(abspath $@) *)