Merge "rust: add aconfig_flag support" into main am: 5ada6c27 am: f73da3ef

Original change: https://android-review.googlesource.com/c/platform/build/soong/+/2863750



Change-Id: I91daf177cc106edd6c36e11b9721c36db5c425ac
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>