JDK-8282532

[Jules W.]

Apologies for not creating a thread consulting the mailing list before
submitting the PR, I'm still getting used to the process (And also thought
this would create unnecessary noise for people within this list).

I initially believed that given how the legacy options had warnings when
they were set, and how they were discouraged in many areas, that they were
eventually to be removed, but that assumption I made appears to be wrong.

I was more concerned about how easy it was to understand what the
option did than the name conformation, --current-platform was the best one
i could come up with so far; --openjdk-build sounded slightly less clear to
me when i was coming up with the name. That aside, I'm not sure if keeping
the old autoconf --build option is possible, since it seems that
--openjdk-target formats --build, --host and --target in a specific order,
and whether using the existing --build option would affect it in any way,
since that would mean --build is now behind --host and --target (Given how
--openjdk-target works, from what I can tell).

I haven't changed the html version of the documentation yet as I haven't
really finished making changes to the markdown version, I do apologize for
the formatting errors though.


best regards,

Julian