s390/pci: use to_pci_dev

Use the to_pci_dev macro to fetch a pci_dev from a struct device
pointer.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/pci/pci_dma.c b/arch/s390/pci/pci_dma.c
index f8e69d5..a2343c1 100644
--- a/arch/s390/pci/pci_dma.c
+++ b/arch/s390/pci/pci_dma.c
@@ -263,7 +263,7 @@
 				     enum dma_data_direction direction,
 				     struct dma_attrs *attrs)
 {
-	struct zpci_dev *zdev = get_zdev(container_of(dev, struct pci_dev, dev));
+	struct zpci_dev *zdev = get_zdev(to_pci_dev(dev));
 	unsigned long nr_pages, iommu_page_index;
 	unsigned long pa = page_to_phys(page) + offset;
 	int flags = ZPCI_PTE_VALID;
@@ -304,7 +304,7 @@
 				 size_t size, enum dma_data_direction direction,
 				 struct dma_attrs *attrs)
 {
-	struct zpci_dev *zdev = get_zdev(container_of(dev, struct pci_dev, dev));
+	struct zpci_dev *zdev = get_zdev(to_pci_dev(dev));
 	unsigned long iommu_page_index;
 	int npages;
 
@@ -323,7 +323,7 @@
 			    dma_addr_t *dma_handle, gfp_t flag,
 			    struct dma_attrs *attrs)
 {
-	struct zpci_dev *zdev = get_zdev(container_of(dev, struct pci_dev, dev));
+	struct zpci_dev *zdev = get_zdev(to_pci_dev(dev));
 	struct page *page;
 	unsigned long pa;
 	dma_addr_t map;