[PATCH v7 03/28] iommu: Use enum iommu_hw_info_type for type in hw_info op

[Tian, Kevin]

> From: Nicolin Chen <nicolinc at nvidia.com>
> Sent: Friday, June 27, 2025 3:35 AM
> 
> Replace u32 to make it clear. No functional changes.
> 
> Also simplify the kdoc since the type itself is clear enough.
> 
> Signed-off-by: Nicolin Chen <nicolinc at nvidia.com>

Reviewed-by: Kevin Tian <kevin.tian at intel.com>