Revert "rust: Use autogenerated Trusty makefile rules" am: c8c514fec6

Original change: https://android-review.googlesource.com/c/trusty/app/keymint/+/2745798

Change-Id: I6dab7c54bdb6c62d0ad5133d42d7081c0867b3b1
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>