Make memchr available to product and vendor am: ae75378e8c am: ea6ce3a6c0

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/memchr/+/2475775

Change-Id: If0a9012e027cd0e128b0e749566333c0c5713b05
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>