removed outdated comment in server.cpp

Former-commit-id: 98f08034a13341059b9b1690989e7ef0207ac920

src/server.cpp

@@ -4635,10 +4635,6 @@ int prepareForShutdown(int flags) {
        overwrite the synchronous saving did by SHUTDOWN. */
     if (g_pserver->child_type == CHILD_TYPE_RDB) {
         serverLog(LL_WARNING,"There is a child saving an .rdb. Killing it!");
-        /* Note that, in killRDBChild, we call rdbRemoveTempFile that will
-         * do close fd(in order to unlink file actully) in background thread.
-         * The temp rdb file fd may won't be closed when redis exits quickly,
-         * but OS will close this fd when process exits. */
         killRDBChild();
         /* Note that, in killRDBChild normally has backgroundSaveDoneHandler
          * doing it's cleanup, but in this case this code will not be reached,