Add build files for strum crate am: abadbccd53 am: 6368cd9a6a

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/strum/+/2924554

Change-Id: I9dbc0ed082d65ac5ef56d6d8604813078403beae
Signed-off-by: Automerger Merge Worker <[email protected]>