drm/amdgpu: Use pci_get_base_class() to reduce duplicated code

Use pci_get_base_class() to reduce duplicated code. No functional change
intended.

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Sui Jingfeng <[e-mail]>
Signed-off-by: Bjorn Helgaas <[e-mail]>
Reviewed-by: Alex Deucher <[e-mail]>
Cc: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c

···
 	struct pci_dev *pdev = NULL;
 	int ret;
 
-	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
-		if (!atif->handle)
-			amdgpu_atif_pci_probe_handle(pdev);
-		if (!atcs->handle)
-			amdgpu_atcs_pci_probe_handle(pdev);
-	}
+	while ((pdev = pci_get_base_class(PCI_BASE_CLASS_DISPLAY, pdev))) {
+		if ((pdev->class != PCI_CLASS_DISPLAY_VGA << 8) &&
+		    (pdev->class != PCI_CLASS_DISPLAY_OTHER << 8))
+			continue;
 
-	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
 		if (!atif->handle)
 			amdgpu_atif_pci_probe_handle(pdev);
 		if (!atcs->handle)

drivers/gpu/drm/amd/amdgpu/amdgpu_bios.c

···
 	if (adev->flags & AMD_IS_APU)
 		return false;
 
-	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
+	while ((pdev = pci_get_base_class(PCI_BASE_CLASS_DISPLAY, pdev))) {
+		if ((pdev->class != PCI_CLASS_DISPLAY_VGA << 8) &&
+		    (pdev->class != PCI_CLASS_DISPLAY_OTHER << 8))
+			continue;
+
 		dhandle = ACPI_HANDLE(&pdev->dev);
 		if (!dhandle)
 			continue;
···
 		if (ACPI_SUCCESS(status)) {
 			found = true;
 			break;
-		}
-	}
-
-	if (!found) {
-		while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
-			dhandle = ACPI_HANDLE(&pdev->dev);
-			if (!dhandle)
-				continue;
-
-			status = acpi_get_handle(dhandle, "ATRM", &atrm_handle);
-			if (ACPI_SUCCESS(status)) {
-				found = true;
-				break;
-			}
 		}
 	}