iommu: Directly use ida_alloc()/free()

Use ida_alloc()/ida_free() instead of deprecated
ida_simple_get()/ida_simple_remove().

Signed-off-by: Ke Liu <liuke94@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20220608021655.1538087-1-liuke94@huawei.com


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