RFR: Removed forwardporting

[Iris Clark]

On Fri, 2 Jun 2023 11:50:46 GMT, Jesper Wilhelmsson <jwilhelm at openjdk.org> wrote:

> @edvbld is out for the next few months so on his request I took over the change from #105. I have updated the patch based on the changes I proposed in my review there.
> 
> This patch removes the instructions related to forwardporting as this is no longer a concept in OpenJDK.

Marked as reviewed by iris (Reviewer).

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PR Review: https://git.openjdk.org/guide/pull/107#pullrequestreview-1457638099