RFR: 8353066: Properly detect Windows/aarch64 as build platform

[Phil Race]

On Wed, 2 Apr 2025 23:25:28 GMT, Magnus Ihse Bursie <ihse at openjdk.org> wrote:

> Configure does not properly detect Windows/aarch64 on Cygwin. One complicating factor here is that no native aarch64 version of Cygwin exists, so it is running x64 binaries in emulated mode.

works for me on Windows 11 aarch64
generated the right configure and the build seems to be doing aarch64 things.

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Marked as reviewed by prr (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/24397#pullrequestreview-2741234059