fix overzealous use of UseEnumValueNameForStringColumns
fix overzealous use of UseEnumValueNameForStringColumns

ronnyek/linq2db,linq2db/linq2db,MaceWindu/linq2db,LinqToDB4iSeries/linq2db,linq2db/linq2db,LinqToDB4iSeries/linq2db,MaceWindu/linq2db