Tentative attempt at disabling ASECs.

Awhile back we explicitly blocked any new ASEC installs, with the
expectation that we'd eventually remove the logic entirely.  Let's
pretend like we ripped the code out and see what (if anything) still
depends on them.

Test: builds, boots
Bug: 32913676
Change-Id: I3b5c624cc0f9e1a71d40af12bee6bc7f7f859e3d