message: Fix linker issue with socket_guard
diff: #include "caf/detail/get_mac_addresses.hpp"
  #include "caf/config.hpp"
  -#include "caf/detail/socket_guard.hpp"
  +#include "caf/detail/scope_guard.hpp"
  #if defined(CAF_MACOS) || defined(CAF_BSD) || defined(CAF_IOS)
  @@ -130,7 +130,9 @@ std::vector<iface_info> get_mac_addresses() {
  perror("socket");
  return {};
  }
  - socket_guard guard{sck};
  + auto g = make_scope_guard([&] {
  + close(sck);
  + });
  // query available interfaces
  char buf[1024] = {0};
  ifconf ifc;
  