GNUmakefile: Swap uname -s with rustc --print host-tuple for cross-build and MSYS

[oech3]

Closes #11252 @ognevny

[ognevny]

after brief look it seems that using rustc target is better!

[oech3]

I'm happy since x86_64-pc-cygwin is not x86_64-pc-windows-cygwin.

[ognevny]

I'm happy since x86_64-pc-cygwin is not x86_64-pc-windows-cygwin.

cygwin is cygwin, windows is windows. for compilers it makes sense

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/date/date-locale-hour (fails in this run but passes in the 'main' branch)
Skipping an intermittent issue tests/date/resolution (passes in this run but fails in the 'main' branch)
Skipping an intermittent issue tests/tty/tty-eof (passes in this run but fails in the 'main' branch)
Note: The gnu test tests/basenc/bounded-memory is now being skipped but was previously passing.

[oech3]

We actually should extract utils from cargo metadata --format-version 1 --no-deps | jq ... but jq dep was rejected.

[codspeed-hq]

Merging this PR will not alter performance

✅ 298 untouched benchmarks
⏩ 48 skipped benchmarks¹

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_{Comparing oech3:make-rustc (52baafa) with main (5a912a7)}

Footnotes

1. 48 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[sylvestre]

can we add a task in the ci to make sure we won't regress? thanks

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/tail/overlay-headers (fails in this run but passes in the 'main' branch)
Skipping an intermittent issue tests/date/date-locale-hour (passes in this run but fails in the 'main' branch)
Congrats! The gnu test tests/rm/many-dir-entries-vs-OOM is now passing!
Congrats! The gnu test tests/seq/seq-epipe is now passing!

[oech3]

added regression test.

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/date/date-locale-hour (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/tail/symlink (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/tty/tty-eof (fails in this run but passes in the 'main' branch)
Skipping an intermittent issue tests/pr/bounded-memory (passes in this run but fails in the 'main' branch)
Congrats! The gnu test tests/unexpand/bounded-memory is now passing!