apkdmverity: enable AndroidTest

The Android test for apkdmverity is now enabled and the binary is
slightly modified to use Android-specific paths (e.g. /dev/block/loopX
instead of /dev/loopX).

Bug: 189785765
Test: cargo test
Test: adb root; adb shell setenforce 0; atest apkdmverity.test
Change-Id: Iaeebbefd961db289af3d2ba7492c1c3110f72c0c
4 files changed