arm: Remove dev->archdata.iommu pointer

There are no users left, all drivers have been converted to use the
per-device private pointer offered by IOMMU core.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Link: https://lore.kernel.org/r/20200625130836.1916-12-joro@8bytes.org

arch/arm/include/asm/device.h

@@ -9,9 +9,6 @@ struct dev_archdata {
 #ifdef CONFIG_DMABOUNCE
 	struct dmabounce_device_info *dmabounce;
 #endif
-#ifdef CONFIG_IOMMU_API
-	void *iommu; /* private IOMMU data */
-#endif
 #ifdef CONFIG_ARM_DMA_USE_IOMMU
 	struct dma_iommu_mapping	*mapping;
 #endif