hw/arm/virt-acpi-build: Re-arrange SMMUv3 IORT build

hw/arm/virt-acpi-build: Re-arrange SMMUv3 IORT build

Introduce a new struct AcpiIortSMMUv3Dev to hold all the information
required for SMMUv3 IORT node and use that for populating the node.

The current machine wide SMMUv3 is named as legacy SMMUv3 as we will
soon add support for user-creatable SMMUv3 devices. These changes will
be useful to have common code paths when we add that support.

Tested-by: Nathan Chen <nathanc@nvidia.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Signed-off-by: Shameer Kolothum <skolothumtho@nvidia.com>
Reviewed-by: Donald Dutile <ddutile@redhat.com>
Message-id: 20250829082543.7680-3-skolothumtho@nvidia.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>