iommu/amd: Remove domain->updated

This struct member was used to track whether a domain
change requires updates to the device-table and IOMMU cache
flushes. The problem is, that access to this field is racy
since locking in the common mapping code-paths has been
eliminated.

Move the updated field to the stack to get rid of all
potential races and remove the field from the struct.

Fixes: 92d420ec

 ("iommu/amd: Relax locking in dma_ops path")
Reviewed-by: Filippo Sironi <sironi@amazon.de>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>