iommu/mediatek: Make use of iommu_device_register interface

Register individual Mediatek IOMMUs to the iommu core and
add sysfs entries.

Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mediatek@lists.infradead.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
diff --git a/drivers/iommu/mtk_iommu.h b/drivers/iommu/mtk_iommu.h
index 50177f7..2a28ead 100644
--- a/drivers/iommu/mtk_iommu.h
+++ b/drivers/iommu/mtk_iommu.h
@@ -47,6 +47,8 @@ struct mtk_iommu_data {
 	struct iommu_group		*m4u_group;
 	struct mtk_smi_iommu		smi_imu;      /* SMI larb iommu info */
 	bool                            enable_4GB;
+
+	struct iommu_device		iommu;
 };
 
 static inline int compare_of(struct device *dev, void *data)