iommu: Fix passthrough option documentation

Document that the default for "iommu.passthrough" is now configurable.

Fixes: 58d1131777 ("iommu: Add config option to set passthrough as default")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This commit is contained in:
Robin Murphy 2018-09-20 14:14:26 +01:00 • committed by Jonathan Corbet
commit 9d723b4ccb