RFR: 8265192: [macos_aarch64] configure script fails if GNU uname in PATH

[Nick Gasson]

With GNU coreutils from Homebrew in the PATH, configure fails on Apple
silicon Macs with:


checking build system type... Invalid configuration `arm64-apple-darwin20.2.0': machine `arm64-apple' not recognized
configure: error: /opt/homebrew/bin/bash /Users/nicgas01/jdk/make/autoconf/build-aux/config.sub arm64-apple-darwin20.2.0 failed
configure exiting with result code 1


The system `uname -p` prints "arm" but GNU's version prints "arm64".
This patch just extends config.guess to handle this case.

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Commit messages:
 - 8265192: [macos_aarch64] configure script fails if GNU uname in PATH

Changes: https://git.openjdk.java.net/jdk/pull/3487/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3487&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8265192
  Stats: 4 lines in 1 file changed: 4 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3487.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3487/head:pull/3487

PR: https://git.openjdk.java.net/jdk/pull/3487