Generate license header with cargo_embargo. am: a54d90d489

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/bitreader/+/3205764

Change-Id: Ie95ce8fbf83f6c99fa50abd648585d79238e0962
Signed-off-by: Automerger Merge Worker <[email protected]>