Rewrite the .data.bimg.rel.ro check in OatFile::Setup().

In preparation for loading boot image extensions before
Runtime::Current()->GetClassLinker() has been initialized,
change the check to not rely on Runtime::Current() at all.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Change-Id: Ica37c294a19e36e615186a0331d4d18c40c7fe2e
2 files changed