[build] Suppress -Wunused-but-set-var in minizip

This patch suppresses -Wunused-but-set-variable warning in
minizip that does not comply with.

The code that causes the issue is as the following:
third_party/zlib/contrib/minizip/zip.c:1476:21: error: variable 'bBreak'
set but not used

Bug: 96410
Change-Id: I903e0d2bdbf672af4d6a300af09a7733aeaf84d2
Reviewed-on: https://fuchsia-review.googlesource.com/c/third_party/zlib/+/664544
Reviewed-by: Shai Barack <shayba@google.com>
1 file changed