cp: fix 2 clippy expections

[oech3]

remove clippy::if_not_else and clippy::unnecessary_cast allow(unused_variables)

[RenjiSann]

Also, it seems that you kept clippy::unnecessary_cast after all, is it expected ?

[oech3]

I typo. I meant allow(unused_variables)

[github-actions]

GNU testsuite comparison:

Note: The gnu test tests/cut/bounded-memory is now being skipped but was previously passing.
Note: The gnu test tests/rm/many-dir-entries-vs-OOM is now being skipped but was previously passing.
Skip an intermittent issue tests/tail/tail-n0f (was skipped on 'main', now failing)

[codspeed-hq]

Merging this PR will degrade performance by 14.24%

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

❌ 2 regressed benchmarks
✅ 337 untouched benchmarks
⏩ 46 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Memory	cp_recursive_deep_tree[(120, 4)]	532.7 KB	699.2 KB	-23.82%
❌	Simulation	ls_recursive_balanced_tree[(6, 4, 15)]	49.4 ms	51.2 ms	-3.44%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing oech3:cp-if-not-else (fae5d40) with main (424fef0)}

Footnotes

1. 46 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. ↩