Reduce core image to 6 modules.

This was
    Revert^2 "Reduce core image to core-{oj,libart,simple}."
but we're now keeping three additional modules, namely
conscrypt, okhttp and bouncycastle. And we fix the boot
class path used by vogar with the companion change
    https://android-review.googlesource.com/840810 .

This reverts commit 00fe35e4.

Change-Id: I6137edd91c03c17be50de200267eb9adc971e8fb
Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Test: Pixel 3 XL boots.
Test: m test-art-target-gtest
Test: testrunner.py --target --optimizing
Test: art/tools/run-libcore-tests.sh --mode=device --variant=X64
Bug: 119868597