Make rand_chacha available to product and vendor am: 63509b91b6

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/rand_chacha/+/2476394

Change-Id: Ifa6000073351b39c7fc0b7c678f99fb485642984
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>