iommu: Consolitate ->add/remove_device() calls

Put them into separate functions and call those where the
plain ops have been called before.

Signed-off-by: Joerg Roedel <jroedel@suse.de>

include/linux/iommu.h

@@ -409,6 +409,9 @@ static inline void dev_iommu_fwspec_set(struct device *dev,
 	dev->iommu_fwspec = fwspec;
 }
 
+int iommu_probe_device(struct device *dev);
+void iommu_release_device(struct device *dev);
+
 #else /* CONFIG_IOMMU_API */
 
 struct iommu_ops {};