Claude review: drm/panfrost: Add bus_ace optional clock support for RZ/G2L

[Claude Code Review Bot <claude-review@example.com>]

Patch Review

This patch adds a `bus_ace_clock` optional clock, wiring it into init, fini, and runtime suspend/resume.

**Bug: Duplicate `err = PTR_ERR(...)` assignment.** In `panfrost_clk_init()`:

```c
+	if (IS_ERR(pfdev->bus_ace_clock)) {
+		err = PTR_ERR(pfdev->bus_ace_clock);
+		dev_err(pfdev->base.dev, "get bus_ace_clock failed %ld\n",
+			PTR_ERR(pfdev->bus_ace_clock));
+		err = PTR_ERR(pfdev->bus_ace_clock);
+		goto disable_bus_clock;
+	}
```

The `err = PTR_ERR(pfdev->bus_ace_clock)` is assigned twice (lines before and after the `dev_err`). This is harmless but clearly a copy-paste error. The first assignment should be removed (keeping it after `dev_err` for consistency with the existing `bus_clock` error block pattern), or the second one removed.

**Inconsistency with bus_clock init pattern.** The existing `bus_clock` init code has a `if (pfdev->bus_clock)` guard around `clk_prepare_enable()` (line 64-71 in the applied code), which also prints the clock rate. The new `bus_ace_clock` code calls `clk_prepare_enable()` unconditionally (which is fine since the clk API handles NULL), but this creates an inconsistency within the same function. Consider either: (a) also removing the NULL guard from the `bus_clock` block for consistency, or (b) matching the existing pattern. This is minor since the API handles NULL, but consistency aids readability.

**Runtime resume error path nesting.** The `clk_enable(pfdev->bus_ace_clock)` call and its error label `err_bus_ace_clk` are placed *inside* the `if (pfdev->comp->pm_features & BIT(GPU_PM_RT))` block, but the error label itself is *outside* the block:

```c
	if (pfdev->comp->pm_features & BIT(GPU_PM_RT)) {
		...
		ret = clk_enable(pfdev->bus_ace_clock);
		if (ret)
			goto err_bus_ace_clk;
	}
	...
	return 0;

err_bus_ace_clk:
	if (pfdev->comp->pm_features & BIT(GPU_PM_RT))
		clk_disable(pfdev->bus_clock);
```

This works because the goto only fires when `GPU_PM_RT` is set, and the error handlers re-check the flag. This matches the existing pattern for `err_bus_clk` and `err_clk`, so it's fine.

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Generated by Claude Code Patch Reviewer