iommu/vt-d: Use for_each_drhd_unit() instead of list_for_each_entry()

Use for_each_drhd_unit() instead of list_for_each_entry for
better readability.

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
1 file changed