RFR: 8298576: Serial: Move some MarkSweep method definitions to cpp

[Albert Mingkun Yang]

On Mon, 12 Dec 2022 13:00:51 GMT, Albert Mingkun Yang <ayang at openjdk.org> wrote:

> Simple change of moving some code from `inline.hpp` to `cpp`.

Thanks for the review.

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

PR: https://git.openjdk.org/jdk/pull/11633