|SUCCESS| [v1] net/mlx5: fix suffix groups without default FDB rule

[dpdklab at iol.unh.edu]

Test-Label: ai-code-review
Test-Status: SUCCESS
https://dpdk.org/patch/171476

_AI Code Review_

=== Patch Review: series.patch (via Claude) ===
Review date: 2026-10-16

# DPDK Patch Review

## Analysis

This patch modifies suffix group calculation in the mlx5 PMD's flow creation logic.
The change makes meter and sample suffix groups conditional on `priv->fdb_def_rule`
being enabled when operating in transfer mode.

## Review

### Errors

None identified.

### Warnings

None identified.

### Info

**Documentation:**
The commit message and code change are clear about the intent.
However, it would be helpful to have a comment in the code explaining the relationship
between `fdb_def_rule` and suffix group adjustment to prevent future confusion.

```c
/* Only decrement suffix groups when FDB default rule is active,
 * as the default rule occupies table level 0. */
sfx_attr.group = (sfx_attr.transfer && priv->fdb_def_rule) ?
		(MLX5_FLOW_TABLE_LEVEL_METER - 1) :
		 MLX5_FLOW_TABLE_LEVEL_METER;
```

This is purely a readability suggestion to document the logic for future maintainers.

Review-Result: CLEAN