Do not run veridex on unbundled app builds

Unbundled app builds do not build the framework, only apps against
the prebuilt public API. Running veridex from the local tree does,
however, depend on the framework to generate the list of non-SDK
APIs. Disable veridex on such builds and remove appcompat.zip from
artifacts.

Test: make ANDROID_BUILDSPEC=vendor/google/build/app_build_spec.mk
Change-Id: I16289adc7fc660109d61260e8a49e992228e727c