remoteproc: Use iommu_paging_domain_alloc()

An iommu domain is allocated in rproc_enable_iommu() and is attached to
rproc->dev.parent in the same function.

Use iommu_paging_domain_alloc() to make it explicit.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Beleswar Padhi <b-padhi@ti.com>
Link: https://lore.kernel.org/r/20241009041147.28391-2-baolu.lu@linux.intel.com


Signed-off-by: Joerg Roedel <jroedel@suse.de>