|WARNING| doc: fix API comments for Doxygen 1.18.0

[dpdklab at iol.unh.edu]

Test-Label: ai-code-review
Test-Status: WARNING
https://dpdk.org/patch/169012

_AI Code Review_

=== Patch Review: series.patch (via Claude) ===
Review date: 2026-09-03

# DPDK Patch Review

## Summary
This patch updates Doxygen comments to fix compatibility issues with Doxygen 1.18.0. The changes address two problems: parentheses in static function references and anonymous struct/union member references.

## Errors

None identified.

## Warnings

None identified.

## Info

### 1. Documentation-only change
This patch contains only documentation updates (Doxygen comment fixes) and no code changes. The modifications are necessary for compatibility with Doxygen 1.18.0 and do not affect functionality.

### 2. Reference format changes are appropriate
The changes from `@ref function()` to `@ref function` (removing parentheses) and from `@ref struct.member` to `@ref struct "member"` are correct workarounds for the Doxygen 1.18.0 issues cited in the commit message.

### 3. Cross-reference verification
The updated references point to valid identifiers:
- `rte_event_port_preschedule_modify` - valid function
- `rte_event` structure fields (`flow_id`, `priority`, `queue_id`, `op`, `impl_opaque`) - valid fields
- `rte_graph_feature_data_*` functions - valid functions (no parentheses needed)
- `rte_graph_feature_arc_mbuf_dynfields_get` - valid function

All reference targets exist in the codebase and the new syntax should resolve correctly in Doxygen 1.18.0.

## Overall Assessment

**APPROVED** - This is a clean documentation fix for Doxygen compatibility. The patch:
- Makes only necessary changes to fix Doxygen 1.18.0 issues
- Updates references consistently throughout affected files
- Does not modify any code or functionality
- Properly targets stable@ for backporting (documentation build fixes are appropriate for stable)

No correctness bugs, style violations, or guideline issues identified.