typo fixed (compilation failure with libwrap)

sql/mysqld.cc

@@ -6207,7 +6207,7 @@ void handle_connections_sockets()
             The connection was refused by TCP wrappers.
             There are no details (by client IP) available to update the host_cache.
           */
-          statistic_increment(connection_tcpwrap_errors, &LOCK_status);
+          statistic_increment(connection_errors_tcpwrap, &LOCK_status);
 	  continue;
 	}
       }