Remove AsyncUDPSocket->getFD

Summary: It's dead.

Reviewed By: yfeldblum

Differential Revision: D14425042

fbshipit-source-id: 098de614955eedd7ccc733858db85b997d01d9e0

folly/io/async/AsyncUDPSocket.h

@@ -195,10 +195,6 @@ class AsyncUDPSocket : public EventHandler {
   /**
    * Get internal FD used by this socket
    */
-  virtual int getFD(int) const {
-    return getNetworkSocket().toFd();
-  }
-
   virtual NetworkSocket getNetworkSocket() const {
     CHECK_NE(NetworkSocket(), fd_) << "Need to bind before getting FD out";
     return fd_;