Remove weak symbol when building with BoringSSL

See https://github.com/netty/netty-tcnative/pull/753 from upstream. We
should remove this unmaintained, outdated copy of netty-tcnative from
Chromium (it's only used in tests) but, in the meantime, fix the build
breakage.

Bug: 1385890
2 files changed
tree: e1316daf4962bea47a86acee2d1a8093ceb28e77
  1. c/
  2. java/