git: 900147a461df..f4695a30267c - vendor/zlib - vendor branch updated

[Xin LI]

The branch vendor/zlib has been updated by delphij:

URL: https://cgit.FreeBSD.org/src/log/?id=900147a461df..f4695a30267c

f4695a30267c Vendor import of zlib 1.3.1.