intel_iommu: Implement stage-1 translation

intel_iommu: Implement stage-1 translation

This adds stage-1 page table walking to support stage-1 only
translation in scalable mode.

Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Co-developed-by: Clément Mathieu--Drif <clement.mathieu--drif@eviden.com>
Signed-off-by: Clément Mathieu--Drif <clement.mathieu--drif@eviden.com>
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20241212083757.605022-7-zhenzhong.duan@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>