RFR: 8323660: Serial: Fix header ordering and indentation [v3]

[Albert Mingkun Yang]

On Fri, 12 Jan 2024 15:26:34 GMT, Lei Zaakjyu <duke at openjdk.org> wrote:

>> follow up 8234502.
>
> Lei Zaakjyu has updated the pull request incrementally with one additional commit since the last revision:
> 
>   fix

Marked as reviewed by ayang (Reviewer).

-------------

PR Review: https://git.openjdk.org/jdk/pull/17398#pullrequestreview-1818513721