[MERGE][1.15.1] use zdll on Windows to build chk_map extension

[Alexander Belchenko]

John Arbash Meinel пишет:
> John Arbash Meinel has voted approve.
> Status is now: Approved
> Comment:
> I'm okay with this, though I'll mention that doing:
> mv zdll.lib z.lib
> 
> causes the existing code to build just fine and depend on zlib1.dll as
> expected. (That is how I'm building things on kerguelen.) As such, this
> will likely break the kerguelen builds, but I can rename the file back.

Well, I'm using official binary distribution of zlib and follow its README.
IMO using official name is better.