Do not use absolute addresses in image test oat files.

We have not been using oat files with absolute addresses
for a long time, except that we forgot to remove code that
creates such files for image tests (gtests). Remove that
code now as well as related code including code that deals
with obsolete `oat_patches` sections.

Test: m test-art-host-gtest
Change-Id: If3e752f01c453e2a2628ac82c3a990c68047610e
6 files changed