iommu: Use right function to get group for device

[ Upstream commit 57274ea25736496ee019a5c40479855b21888839 ]

The iommu_group_get_for_dev() will allocate a group for a
device if it isn't in any group. This isn't the use case
in iommu_request_dm_for_dev(). Let's use iommu_group_get()
instead.

Fixes: d290f1e70d85a ("iommu: Introduce iommu_request_dm_for_dev()")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 71b89e4..dbcc13e 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1582,9 +1582,9 @@
 	int ret;
 
 	/* Device must already be in a group before calling this function */
-	group = iommu_group_get_for_dev(dev);
-	if (IS_ERR(group))
-		return PTR_ERR(group);
+	group = iommu_group_get(dev);
+	if (!group)
+		return -EINVAL;
 
 	mutex_lock(&group->mutex);