iommu: Deprecate Intel and AMD cmdline methods to enable strict mode

Now that the x86 drivers support iommu.strict, deprecate the custom
methods.

Signed-off-by: John Garry <john.garry@huawei.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/1626088340-5838-2-git-send-email-john.garry@huawei.com


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