MDEV-32798 innodb_fast_shutdown=0 hang after incomplete startup

innodb_preshutdown(): Only wait for active transactions to be terminated
if InnoDB was started and innodb_force_recovery=3 or larger does not
prevent a rollback.

This fixes the following:

./mtr --parallel=auto --mysqld=--innodb-fast-shutdown=0 \
innodb.log_file_size innodb.innodb_force_recovery \
innodb.read_only_recovery innodb.read_only_recover_committed \
mariabackup.apply-log-only-incr

storage/innobase/srv/srv0start.cc

@@ -1995,7 +1995,7 @@ void innodb_preshutdown()
     better prevent any further changes from being buffered. */
     innodb_change_buffering= 0;
 
-    if (trx_sys.is_initialised())
+    if (srv_force_recovery < SRV_FORCE_NO_TRX_UNDO && srv_was_started)
       while (trx_sys.any_active_transactions())
         os_thread_sleep(1000);
   }