PCI: Rename _DSM constants to align with spec

Rename PCI-related _DSM constants to align them with the PCI Firmware Spec,
r3.2, sec 4.6.  No functional change intended.

Link: https://lore.kernel.org/r/20200526213905.2479381-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/acpi/pci_root.c

@@ -938,7 +938,7 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
 	 * assignments made by firmware for this host bridge.
 	 */
 	obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 1,
-	                        IGNORE_PCI_BOOT_CONFIG_DSM, NULL);
+				DSM_PCI_PRESERVE_BOOT_CONFIG, NULL);
 	if (obj && obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 0)
 		host_bridge->preserve_config = 1;
 	ACPI_FREE(obj);