Merge "Remove code about mixed sepolicy build" into main am: 3c7a4232

Original change: https://android-review.googlesource.com/c/platform/build/+/2734338



Change-Id: Ib7f7344c4b493afe0e70603f069a20b04cd4c90e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>