src: fix windows build error

Fix a Windows-only build error that was introduced in
commit 1183ba4 ("zlib: support concatenated gzip files").

Rename the NO_ERROR and FAILED enumerations, they conflict
with macros of the same name in <winerror.h>.

PR-URL: https://github.com/node-forward/node/pull/57
Reviewed-By: Fedor Indutny <fedor@indutny.com>
Reviewed-By: Rod Vagg <rod@vagg.org>