iommu/amd: Add missing spin_lock initialization

Add missing spin_lock initialization in
amd_iommu_bind_pasid() function and make lockdep happy
again.

Cc: stable@vger.kernel.org # >= v3.3
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/drivers/iommu/amd_iommu_v2.c b/drivers/iommu/amd_iommu_v2.c
index 036fe9b..a1f1bc8 100644
--- a/drivers/iommu/amd_iommu_v2.c
+++ b/drivers/iommu/amd_iommu_v2.c
@@ -681,6 +681,8 @@
 
 	atomic_set(&pasid_state->count, 1);
 	init_waitqueue_head(&pasid_state->wq);
+	spin_lock_init(&pasid_state->lock);
+
 	pasid_state->task         = task;
 	pasid_state->mm           = get_task_mm(task);
 	pasid_state->device_state = dev_state;