Minor bug in s3file.go causes unnecessary requests to s3

[guliyevemil1]

In s3file.go, on line 574, we have

    if newPosition == f.position {
        req.ch <- response{off: f.position}
    }

and it looks like the intended code was supposed to have a return statement like this:

    if newPosition == f.position {
        req.ch <- response{off: f.position}
        return
    }

[yasushi-saito]

Yes, you are right. Thanks for pointing out.