Generate apex_available from c2a instead of a patch am: b7aefdc050 am: a172325fac am: 0c1f704f00

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/unicode-bidi/+/1688683

Change-Id: I986f0e47db893865817587efd2a280521a29ddd9