RFR: 8304364: [AIX] Build erroneously determines build disk is non-local when using GNU-utils df on AIX

[Tyler Steele]

On Thu, 16 Mar 2023 18:55:34 GMT, Tyler Steele <tsteele at openjdk.org> wrote:

> The GNU-utils df command supports a flag `-l` which displays information about local disks only. The AIX df equivalent is `-T local`. However, my build systems uses GNU-utils on AIX. In this case, the build system uses `df -T local`, and incorrectly determines that the disk is non-local from the error code.
> 
> This change corrects that issue by testing if the enabled version of df returns cleanly with the `-T local` flag when AIX is the detected OS. If it does, `-T local` is used, and if not, it defaults to `-l`.
> 
> @erikj79 Thanks for your review on #13065. I pushed to the wrong branch by mistake, and it seems I must now re-create the PR to fix the issue.

I consider one review sufficient for these changes. They are simple, AIX only, and the risk of any non-recoverable failure is quite low.

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PR Comment: https://git.openjdk.org/jdk/pull/13066#issuecomment-1476587925