Claude review: accel/ivpu: Test for imported buffers with drm_gem_is_imported()

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

Patch Review

**Correctness:** The two changes are semantically identical to the code they replace. `drm_gem_is_imported()` (defined at `include/drm/drm_gem.h:646`) is simply `return !!obj->import_attach`, so:

1. `!bo->base.base.import_attach` → `!drm_gem_is_imported(&bo->base.base)` — equivalent, since `!` on a pointer is the same as `!` on `!!pointer`.

2. `bo->base.base.import_attach` → `drm_gem_is_imported(&bo->base.base)` — equivalent truthiness test.

**Consistency with existing codebase:** The ivpu driver already uses `drm_gem_is_imported()` in three other places in the same file (`ivpu_gem.c:34`, `ivpu_gem.c:317`, `ivpu_gem.c:552` on drm-next), so these two call sites were stragglers. This patch brings full consistency.

**Minor note:** In the second hunk at `ivpu_bo_unbind_locked`, the very next line still uses `bo->base.base.import_attach` directly:
```c
if (drm_gem_is_imported(&bo->base.base)) {
    dma_buf_unmap_attachment(bo->base.base.import_attach,
                             bo->base.sgt, DMA_BIDIRECTIONAL);
```
This is correct — `dma_buf_unmap_attachment()` needs the actual `import_attach` pointer as a value, not a boolean test, so there's no accessor to replace there.

**Verdict:** Clean, correct, minimal patch. No concerns.

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Generated by Claude Code Patch Reviewer