Claude review: drm/xe/xe_drm_ras: Add support for XE DRM RAS

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

Patch Review

**Concern: `kasprintf` device_name not managed by drm**

```c
device_name = kasprintf(GFP_KERNEL, "%04x:%02x:%02x.%d",
                        pci_domain_nr(pdev->bus), pdev->bus->number,
                        PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn));
```

This uses plain `kasprintf` but nodes are allocated with `drmm_kcalloc`. Why not use `pci_name(pdev)` which returns a stable string that doesn't need to be freed? This would eliminate the `kfree(node->device_name)` in cleanup and simplify the code. `pci_name()` returns exactly the same format string.

**Concern: `register_nodes` error path doesn't unregister previously registered nodes**

```c
for_each_error_severity(i) {
    ...
    ret = drm_ras_node_register(node);
    if (ret) {
        cleanup_node_param(ras, i);
        return ret;
    }
}
```

If the second node registration fails, the first successfully registered node is never unregistered. The error path only cleans up the current iteration's parameters, not previously registered nodes.

**Minor: Name mapping macros in uAPI header**

```c
#define DRM_XE_RAS_ERROR_SEVERITY_NAMES { ... }
#define DRM_XE_RAS_ERROR_COMPONENT_NAMES { ... }
```

Placing array initializer macros in a uAPI header is unusual. These are kernel-internal lookup tables, not something userspace typically needs as C macros (userspace would use the netlink string attributes). Consider moving them to an internal header.

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Generated by Claude Code Patch Reviewer