scsi: megaraid_sas: 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 manually. Use pci_dev_id() to simplify
the code a little bit.

Signed-off-by: Jialin Zhang <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Martin K. Petersen <[e-mail]>

drivers/scsi/megaraid/megaraid_sas_base.c

···
 	 */
 	instance->pdev = pdev;
 	instance->host = host;
-	instance->unique_id = pdev->bus->number << 8 | pdev->devfn;
+	instance->unique_id = pci_dev_id(pdev);
 	instance->init_id = MEGASAS_DEFAULT_INIT_ID;
 
 	megasas_set_adapter_type(instance);