Follow-up for Bug #55930 Assertion `thd->transaction.stmt.is_empty()

                         || thd->in_sub_stmt || (thd->state..

Don't rollback statement transactions if we are in a sub-statement.
This could for example happen for open_ltable() when opening the
general log during execution of a stored procedure.

sql/sql_base.cc

@@ -5320,7 +5320,8 @@ TABLE *open_ltable(THD *thd, TABLE_LIST *table_list, thr_lock_type lock_type,
 end:
   if (table == NULL)
   {
-    trans_rollback_stmt(thd);
+    if (!thd->in_sub_stmt)
+      trans_rollback_stmt(thd);
     close_thread_tables(thd);
   }
   thd_proc_info(thd, 0);