cxl/pci: Replace host_bridge->native_aer with pcie_aer_is_native()

Use pcie_aer_is_native() to determine the native AER ownership as the
usage of host_bride->native_aer does not cover command line override of
AER ownership.

Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Reviewed-by: Robert Richter <rrichter@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20230823234305.27333-4-Smita.KoralahalliChannabasappa@amd.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/cxl/pci.c

@@ -529,7 +529,6 @@ static int cxl_pci_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type,
 
 static int cxl_pci_ras_unmask(struct pci_dev *pdev)
 {
-	struct pci_host_bridge *host_bridge = pci_find_host_bridge(pdev->bus);
 	struct cxl_dev_state *cxlds = pci_get_drvdata(pdev);
 	void __iomem *addr;
 	u32 orig_val, val, mask;
@@ -542,7 +541,7 @@ static int cxl_pci_ras_unmask(struct pci_dev *pdev)
 	}
 
 	/* BIOS has PCIe AER error control */
-	if (!host_bridge->native_aer)
+	if (!pcie_aer_is_native(pdev))
 		return 0;
 
 	rc = pcie_capability_read_word(pdev, PCI_EXP_DEVCTL, &cap);