unexpand: Refactor functions to use less parameters

[cerdelen]

Follow up to #10831 (comment) i bundled parameters that belong to each other into a helper struct to reduce function parameters and get rid of the linter exception.

[codspeed-hq]

Merging this PR will degrade performance by 6.7%

❌ 2 regressed benchmarks
✅ 282 untouched benchmarks
⏩ 38 skipped benchmarks¹

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	unexpand_many_lines[100000]	189.7 ms	203.4 ms	-6.7%
❌	Simulation	unexpand_large_file[10]	397.7 ms	426.3 ms	-6.7%

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_{Comparing cerdelen:unexpand_refactor (362c08d) with main (dec633c)}

Footnotes

1. 38 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. ↩

[github-actions]

GNU testsuite comparison:

GNU test failed: tests/pr/bounded-memory. tests/pr/bounded-memory is passing on 'main'. Maybe you have to rebase?
Skip an intermittent issue tests/tail/inotify-dir-recreate (fails in this run but passes in the 'main' branch)
Congrats! The gnu test tests/factor/t10 is no longer failing!
Congrats! The gnu test tests/factor/t34 is no longer failing!
Note: The gnu test tests/cut/bounded-memory is now being skipped but was previously passing.
Note: The gnu test tests/tail/tail-n0f is now being skipped but was previously passing.
Congrats! The gnu test tests/printf/printf-surprise is now passing!

[oech3]

Is this performance regression caused by codegen-units=1 by over killed inline extraction too?