Mount adopted storage after boot completed

Ensure we set up adopted devices after boot complete to avoid
interactions with checkpointing

Test: sm set-force-adoptable on
      sm set-virtual-disk true
      then set up virtual disk
      atest android.appsecurity.cts.AdoptableHostTest
Change-Id: I4cc79a6d8a2d231c739a2b8cae1c1f8e7616ca81