rubyPackages.eventmachine: fix darwin build

This fixes the build of mailcatcher (and maybe others).

Fixes:
```
em.cpp:1232:40: error: invalid operands to binary expression ('__bind<int &, sockaddr *&, int &>' and 'int')
                if (bind (sd, bind_to, bind_to_size) < 0) {
                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^ ~
```
Where `bind` is treated as `std::bind` rather than `::bind` in newer C++
standards.

0 files changed, 0 insertions, 0 deletions