Claude review: drm/atomic: don't set colorop properties of inactive color pipelines

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

Patch Review

**Assessment: Good, one concern about goto label scope**

This patch adds validation in `drm_atomic_set_property()` to reject attempts to set properties on colorops that are not part of the currently active color pipeline. The logic is straightforward:

```c
plane_state = drm_atomic_get_plane_state(state, colorop->plane);
...
for (active_colorop = plane_state->color_pipeline;
     active_colorop;
     active_colorop = active_colorop->next) {
    if (active_colorop == colorop) {
        colorop_state = drm_atomic_get_colorop_state(state, colorop);
        ...
        break;
    }
}

if (!colorop_state) {
    ...
    ret = -EINVAL;
    goto err;
}
```

**Concern**: The `err:` label is added *after* the closing brace of the `default:` case and before the common cleanup code `drm_property_change_valid_put(prop, ref)`. This means that `goto err` from the COLOROP case will still correctly call `drm_property_change_valid_put()`, which is the intended behavior. However, the label is structurally placed outside the switch statement, which means any future code adding error paths in *other* cases might accidentally use this label. This isn't a bug today, but the asymmetry (only the COLOROP case uses `goto err`, all other cases use `break`) is worth noting. An alternative would be to set `ret = -EINVAL` and `break` instead of `goto err`, since both paths end up at `drm_property_change_valid_put()` anyway.

**Observation**: The call to `drm_atomic_get_plane_state()` here means that any userspace attempt to set a colorop property will also pull in the plane state, even if the set ultimately fails. This is a new side effect but probably fine since plane state is cheap and necessary for the validation.

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Generated by Claude Code Patch Reviewer