Remove fd overload of AsyncServerSocket::useExistingSocket

Summary: All calls have been converted to the NetworkSocket overload

Reviewed By: yfeldblum

Differential Revision: D13566829

fbshipit-source-id: c6a3b155ffe35534c0297eba7819413e4ce77282

folly/io/async/AsyncServerSocket.h

@@ -299,9 +299,6 @@ class AsyncServerSocket : public DelayedDestruction, public AsyncSocketBase {
    * On error a TTransportException will be thrown and the caller will retain
    * ownership of the file descriptor.
    */
-  void useExistingSocket(int fd) {
-    useExistingSocket(NetworkSocket::fromFd(fd));
-  }
   void useExistingSocket(NetworkSocket fd);
   void useExistingSockets(const std::vector<NetworkSocket>& fds);