intel_iommu: fix FRCD construction macro

intel_iommu: fix FRCD construction macro

The constant must be unsigned, otherwise the two's complement
overrides the other fields when a PASID is present.

Fixes: 1b2b12376c8a ("intel-iommu: PASID support")
Signed-off-by: Clément Mathieu--Drif <clement.mathieu--drif@eviden.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Minwoo Im <minwoo.im@samsung.com>
Message-Id: <20240709142557.317271-2-clement.mathieu--drif@eviden.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>