Upgrade libavc to v1.4.0 am: 6e8f8ec91d

Original change: https://android-review.googlesource.com/c/platform/external/libavc/+/3058982

Change-Id: I28d75f87779db39528b3f26e18b4a5426c6e8b76
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>