Cygwin: FIFO: remove the arm method

There's no reason to check for errors when we set read_ready or
write_ready.  We don't do that for other events.

winsup/cygwin/fhandler.h

@@ -1343,7 +1343,6 @@ public:
   void set_close_on_exec (bool val);
   void __reg3 raw_read (void *ptr, size_t& ulen);
   ssize_t __reg3 raw_write (const void *ptr, size_t ulen);
-  bool arm (HANDLE h);
   bool need_fixup_before () const { return reader; }
   int fixup_before_fork_exec (DWORD) { stop_listen_client (); return 0; }
   void init_fixup_before ();

winsup/cygwin/fhandler_fifo.cc

@@ -93,28 +93,6 @@ sec_user_cloexec (bool cloexec, PSECURITY_ATTRIBUTES sa, PSID sid)
   return cloexec ? sec_user_nih (sa, sid) : sec_user (sa, sid);
 }
 
-bool inline
-fhandler_fifo::arm (HANDLE h)
-{
-#ifdef DEBUGGING
-  const char *what;
-  if (h == read_ready)
-    what = "reader";
-  else
-    what = "writer";
-  debug_only_printf ("arming %s", what);
-#endif
-
-  bool res = SetEvent (h);
-  if (!res)
-#ifdef DEBUGGING
-    debug_printf ("SetEvent for %s failed, %E", what);
-#else
-    debug_printf ("SetEvent failed, %E");
-#endif
-  return res;
-}
-
 static HANDLE
 create_event ()
 {
@@ -348,11 +326,7 @@ fhandler_fifo::listen_client_thread ()
 	api_fatal ("Can't add a client handler, %E");
 
       /* Allow a writer to open. */
-      if (!arm (read_ready))
-	{
-	  __seterrno ();
-	  goto out;
-	}
+      SetEvent (read_ready);
 
       /* Listen for a writer to connect to the new client handler. */
       fifo_client_handler& fc = fc_handler[nhandlers - 1];
@@ -555,10 +529,8 @@ fhandler_fifo::open (int flags, mode_t)
 	  if (NT_SUCCESS (status))
 	    {
 	      set_pipe_non_blocking (get_handle (), flags & O_NONBLOCK);
-	      if (!arm (write_ready))
-		res = error_set_errno;
-	      else
-		res = success;
+	      SetEvent (write_ready);
+	      res = success;
 	      goto out;
 	    }
 	  else if (STATUS_PIPE_NO_INSTANCE_AVAILABLE (status))