[PATCH] iommu: Fix passthrough option documentation

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

Fixes: 58d1131777a4 ("iommu: Add config option to set passthrough as default")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---

Joerg, Jon, as a pure doc fix I'll leave it to your discretion as to
whose tree is most appropriate (it shouldn't conflict with the other
IOMMU patches I'm working on)

 Documentation/admin-guide/kernel-parameters.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 406b91759b62..8ab2984692ff 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt

@@ -1767,7 +1767,7 @@
 			Format: { "0" | "1" }
 			0 - Use IOMMU translation for DMA.
 			1 - Bypass the IOMMU for DMA.
-			unset - Use IOMMU translation for DMA.
+			unset - Use value of CONFIG_IOMMU_DEFAULT_PASSTHROUGH.
 
 	io7=		[HW] IO7 for Marvel based alpha systems
 			See comment before marvel_specify_io7 in

-- 
2.19.0.dirty