MDEV-22781 CREATE VIEW containing WITH clause Signal 11

For table references to CTEs the field TABLE_LIST::db must be set to
an empty string as it's done for table references to derived tables in
order CTEs to be processed similar to how derived tables are processed.

Approved by Oleksandr Byelkin <sanja@mariadb.com>

sql/sql_cte.cc

@@ -227,6 +227,7 @@ With_element *With_clause::find_table_def(TABLE_LIST *table,
         !table->is_fqtn)
     {
       table->set_derived();
+      table->db= empty_c_string;
       return with_elem;
     }
   }