Fix a failing assert when running funcs_1.innodb_trig_03 test.

The failure was introduced by a precursor patch for the
fix for Bug#52044.

When opening tables for GRANT statement
to check that subject columns exist,
mysql_table_grant() would try to lock the
tables, and thus start a transaction.
This was unnecessary and lead to an assert.

sql/sql_acl.cc

@@ -3072,7 +3072,7 @@ int mysql_table_grant(THD *thd, TABLE_LIST *table_list,
       class LEX_COLUMN *column;
       List_iterator <LEX_COLUMN> column_iter(columns);
 
-      if (open_and_lock_tables(thd, table_list, TRUE, 0))
+      if (open_normal_and_derived_tables(thd, table_list, 0))
         DBUG_RETURN(TRUE);
 
       while ((column = column_iter++))