Remove unnecessary confusing use of $(intermediate).

Change-Id: I0e73c3c1bf94540419e1fd227a3096da148e2459
diff --git a/core/Makefile b/core/Makefile
index 5b26958..81f80fd 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -1280,10 +1280,7 @@
 otatools: $(OTATOOLS)
 
 BUILT_OTATOOLS_PACKAGE := $(PRODUCT_OUT)/otatools.zip
-$(BUILT_OTATOOLS_PACKAGE): \
-	intermediate := $(call intermediates-dir-for,PACKAGING,otatools)
-$(BUILT_OTATOOLS_PACKAGE): \
-	zip_root := $(intermediate)/otatools
+$(BUILT_OTATOOLS_PACKAGE): zip_root := $(call intermediates-dir-for,PACKAGING,otatools)/otatools
 
 $(BUILT_OTATOOLS_PACKAGE): $(OTATOOLS) | $(ACP)
 	@echo "Package OTA tools: $@"