Claude review: drm/atomic: Drop private obj state allocation

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

Patch Review

Removes the `atomic_create_state` call from `drm_atomic_private_obj_init()` since `drm_mode_config_create_state()` (called from `drm_dev_register()`) now handles it.

**Potential ordering concern**: `drm_atomic_private_obj_init()` may be called before `drm_dev_register()`. Between these calls, `obj->state` will be NULL. If any code accesses `obj->state` during driver setup (between init and register), this would crash. The patch relies on `drm_mode_config_create_state()` checking `if (privobj->state) continue;` which is fine for the new flow, but could break drivers that currently depend on the state being available immediately after `drm_atomic_private_obj_init()`.

The current tree already has the `atomic_create_state` call inside `drm_atomic_private_obj_init` -- removing it changes the contract for all callers. This is a semantic change that should be called out more explicitly and might need a wider audit of callers.

Also note: `drm_atomic_private_obj_fini()` unconditionally calls `obj->funcs->atomic_destroy_state(obj, obj->state)` -- if `obj->state` is NULL at teardown time (e.g., if `drm_dev_register` is never called after init), this will crash.

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Generated by Claude Code Patch Reviewer