Migrate to cargo_embargo. am: e24e2e4e2e am: 7d368e0e9d am: 6ac1b5b4bc

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/smccc/+/2828012

Change-Id: I25c80258004c37bc0c024257b148f555e1cabd6c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>