zlib: fix windowBits validation to allow 0 for decompression mode

From the zlib v1.2.11 manual:

> ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
>                                      int  windowBits));
>
> ...
> windowBits can also be zero to request that inflate use the window
> size in the zlib header of the compressed stream.

The current validation of windowBits in zlib.js doesn't check for this
case.

PR-URL: https://github.com/nodejs/node/pull/19686


Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>