Don't call block checkpoint functions above dm-default-key

Bug: 156225476
Test: Build for f2fs and ext4 device, make sure checkpoints roll back
and commit

Merged-In: I7a772ff712dec9e69df175de840d69d296c65923
Change-Id: I7a772ff712dec9e69df175de840d69d296c65923
2 files changed