conn.WriteTo(w io.Writer) 返回值问题

[JemmyH]

Describe the bug
这里的返回值应该是 n + int64(m) ？

To Reproduce
Steps to reproduce the behavior:
None

Expected behavior
应该返回 n + int64(m)

func (c *conn) WriteTo(w io.Writer) (n int64, err error) {
	if c.inboundBuffer.IsEmpty() {
		var m int
		m, err = w.Write(c.buffer)
		c.buffer = c.buffer[m:]
		return int64(m), err
	}
	n, err = c.inboundBuffer.WriteTo(w)
	if err != nil {
		return
	}
	var m int
	m, err = w.Write(c.buffer)
	c.buffer = c.buffer[m:]
	return n + int64(m), err
}

Screenshots
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System Info (please fill out the following information):

• OS (e.g. Ubuntu 18.04): macOS 12.2.1
• Go version (e.g. Go 1.13): go1.17.5 darwin/amd64
• gnet version (e.g. v1.0.0): v2

Additional context
Add any other context about the problem here.

[panjf2000]

这里的确有问题，我晚点改一下。

[panjf2000]

或者你有时间的话也可以提一个 PR。