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

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

Change-Id: I12958b984364a248df33681c526fd78a8008cd2a