deps: fix CLEAR_HASH macro to be usable as a single statement

Apply unreleased (as of zlib v1.2.11) patch from upstream:
- https://github.com/madler/zlib/commit/38e8ce32afbaa82f67d992b9f3056f281fe69259

Original commit message:
  Fix CLEAR_HASH macro to be usable as a single statement.

  As it is used in deflateParams().

PR-URL: https://github.com/nodejs/node/pull/11616


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>