iommu/tegra-gart: fix spin_unlock in map failure path

This must have been messed up while merging, the intention was
clearly to unlock there.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c
index b21598f..779306e 100644
--- a/drivers/iommu/tegra-gart.c
+++ b/drivers/iommu/tegra-gart.c
@@ -246,7 +246,7 @@
 	pfn = __phys_to_pfn(pa);
 	if (!pfn_valid(pfn)) {
 		dev_err(gart->dev, "Invalid page: %08x\n", pa);
-		spin_lock_irqsave(&gart->pte_lock, flags);
+		spin_unlock_irqrestore(&gart->pte_lock, flags);
 		return -EINVAL;
 	}
 	gart_set_pte(gart, iova, GART_PTE(pfn));