drm/rockchip: dw-dp: ratelimit AUX timeout logging

[SuperKali]

On a YY3588 the DP0 port is a USB-C DP Alt Mode output. With nothing plugged in, the boot log fills with about 128 lines from the AUX probe:

dw-dp fde50000.dp: AUX timeout, resetting (cmd=0x9 addr=0x0)
dw-dp fde50000.dp: AUX timeout after recovery: cmd=0x9 addr=0x0 size=1, AUX_STATUS=0x0

Every DPCD access times out because there is no sink, and each failed transfer logs one warning for the reset and one info line after recovery. Sixty-four failed transfers at boot means well over a hundred lines for a condition that is completely normal (no cable).

This ratelimits the reset warning and demotes the post-recovery message to debug. Callers already handle the returned -ETIMEDOUT, so nothing else changes.

Tested on a YY3588 (EVB7 V11, vendor kernel 6.1.115): the AUX flood drops from 128 lines to about 20 ratelimited warnings, and DP output on a connected sink is unaffected.

[coderabbitai]

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Run ID: 4b3cff20-41e4-4d1a-b248-69e6979f03bd

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Reviewing files that changed from the base of the PR and between 1cd878b and cbc1a61.

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• drivers/gpu/drm/rockchip/dw-dp.c

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Walkthrough

This change modifies logging behavior in the dw_dp_aux_transfer() function within the Rockchip DisplayPort driver. The initial AUX timeout warning now uses dev_warn_ratelimited() instead of dev_warn(), and the post-recovery AUX timeout message now uses dev_dbg() instead of dev_info(). No functional logic, exported entities, or public interfaces were altered.

Estimated code review effort: 1 (Trivial) | ~2 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: ratelimiting dw-dp AUX timeout logging.
Description check	✅ Passed	The description matches the change and explains the logging reduction and unchanged timeout handling.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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