Clear LOCAL_BUILT_MODULE_NOT_COPIED between modules

This makes sure that built libraries actually are removed on
ndk-build clean, from projects that include prebuilt static
libraries.

Change-Id: I5e58e82cab062a79d6609f9a8fb18acbec1a1a38
diff --git a/build/core/definitions.mk b/build/core/definitions.mk
index 8d4c687..b9d4d46 100644
--- a/build/core/definitions.mk
+++ b/build/core/definitions.mk
@@ -396,6 +396,7 @@
     FILTER_ASM \
     CPP_FEATURES \
     SHORT_COMMANDS \
+    BUILT_MODULE_NOT_COPIED \
 
 # The following are generated by the build scripts themselves