Revert "rust: Use autogenerated Trusty makefile rules" am: 3ab4ebd693

Original change: https://android-review.googlesource.com/c/trusty/app/sample/+/2745951

Change-Id: I02e353a6433043d9af859dab34ad70ffc08e2a77
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>