Merge "Free input buffers only when released by encoder in avc_enc_fuzzer" am: f5d0c99fa9

Original change: https://android-review.googlesource.com/c/platform/external/libavc/+/1505471

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I3eadf3c6a81f2a4b65ed6110a279341bb58ad52e