Claude review: media: nvidia: tegra-vde: Fix iommu_map_sgtable() return value check

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

Patch Review

**Status: Good**

Same pattern as patch 1: introduces `ssize_t map_err`, checks `< 0`, propagates the real error instead of hardcoded `-ENXIO`:

```c
+	ssize_t map_err;
...
+	map_err = iommu_map_sgtable(vde->domain, addr, sgt,
+				    IOMMU_READ | IOMMU_WRITE);
+	if (map_err < 0) {
 		__free_iova(&vde->iova, iova);
-		return -ENXIO;
+		return map_err;
```

The function returns `int`, and `return map_err` narrows `ssize_t` to `int` -- safe on the error path.

Note that the old code reused `size` for both the input size parameter and the `iommu_map_sgtable` return. The new code avoids that reuse by using a separate `map_err` variable, which is cleaner since `size` continues to be needed later (it's used as a parameter on line 22 and for iova allocation on line 31).

No issues.

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Generated by Claude Code Patch Reviewer