time: obsolete comment in zoneinfo.go

[wzzhu]

Obsolete comment in src/time/zoneinfo.go

// the start and end times bracketing sec when that zone is in effect,
// the offset in seconds east of UTC (such as -5*60*60), and whether
// the daylight savings is being observed at that time.
func (l *Location) lookup(sec int64) (name string, offset int, isDST bool, start, end int64)

should removed the last one
"and whether the daylight savings is being observed at that time".

Caused by this change:
"remove some unused return parameters" https://cs.opensource.google/go/go/+/8da180f6cac51f6cb8a316b962f797dbaf7ee96f

[tklauser]

The isDST return value was added again in https://golang.org/cl/264077, so incidentally the godoc comment is correct again.

[cherrymui]

As @tklauser pointed out, this works as intended now. Thanks.