Add visibility to vendor and subdirectories am: 3a967ce03a

Original change: https://android-review.googlesource.com/c/platform/external/boringssl/+/2987431

Change-Id: I515a9f4f4a7265756f575c06926ca1bfc85b5612
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>