Merge "Null-terminate libselinux context name in fuzzer." am: 0e8eccd069 am: d157a3e180 am: c1272f7cd2 am: 27a10d501b

Original change: https://android-review.googlesource.com/c/platform/external/selinux/+/1492196

Change-Id: I623d2e88390ad2eb2de02a92ccb3c9e0e763c293