Use libarttest(d)_external to fix 656-annotation-lookup-generic-jni,
and enable it on target again.

Test: art/test/testrunner/testrunner.py --target --64 656
      in armv8 target chroot
Test: art/test/testrunner/testrunner.py --host 656
Bug: 186654484
Change-Id: I4cd3dde548aa30afe46c249bc79e36aa952a4aae
5 files changed