x86/pci/XEN: Use PCI device property

instead of fiddling with MSI descriptors.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20211210221813.311410967@linutronix.de

arch/x86/pci/xen.c

@@ -399,9 +399,7 @@ static void xen_teardown_msi_irqs(struct pci_dev *dev)
 
 static void xen_pv_teardown_msi_irqs(struct pci_dev *dev)
 {
-	struct msi_desc *msidesc = first_pci_msi_entry(dev);
-
-	if (msidesc->pci.msi_attrib.is_msix)
+	if (dev->msix_enabled)
 		xen_pci_frontend_disable_msix(dev);
 	else
 		xen_pci_frontend_disable_msi(dev);
@@ -417,10 +415,7 @@ static int xen_msi_domain_alloc_irqs(struct irq_domain *domain,
 	if (WARN_ON_ONCE(!dev_is_pci(dev)))
 		return -EINVAL;
 
-	if (first_msi_entry(dev)->pci.msi_attrib.is_msix)
-		type = PCI_CAP_ID_MSIX;
-	else
-		type = PCI_CAP_ID_MSI;
+	type = to_pci_dev(dev)->msix_enabled ? PCI_CAP_ID_MSIX : PCI_CAP_ID_MSI;
 
 	return xen_msi_ops.setup_msi_irqs(to_pci_dev(dev), nvec, type);
 }