dmaengine: ioatdma: use pci_dev_id() to simplify the code

PCI core API pci_dev_id() can be used to get the BDF number for a pci
device. We don't need to compose it mannually. Use pci_dev_id() to
simplify the code a little bit.
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20230815023821.3518007-1-zhangjialin11@huawei.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/ioat/dca.c

@@ -51,7 +51,7 @@
 /* pack PCI B/D/F into a u16 */
 static inline u16 dcaid_from_pcidev(struct pci_dev *pci)
 {
-	return (pci->bus->number << 8) | pci->devfn;
+	return pci_dev_id(pci);
 }
 
 static int dca_enabled_in_bios(struct pci_dev *pdev)