iommu/fsl: Make use of domain_alloc and domain_free

Implement domain_alloc and domain_free iommu-ops as a
replacement for domain_init/domain_destroy.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
diff --git a/drivers/iommu/fsl_pamu_domain.h b/drivers/iommu/fsl_pamu_domain.h
index c90293f..f2b0f741 100644
--- a/drivers/iommu/fsl_pamu_domain.h
+++ b/drivers/iommu/fsl_pamu_domain.h
@@ -71,7 +71,7 @@
 	u32				stash_id;
 	struct pamu_stash_attribute	dma_stash;
 	u32				snoop_id;
-	struct iommu_domain		*iommu_domain;
+	struct iommu_domain		iommu_domain;
 	spinlock_t			domain_lock;
 };