vfio-pci: Loosen sanity checks to allow future features

VFIO_PCI_NUM_REGIONS and VFIO_PCI_NUM_IRQS should never have been
used in this manner as it locks a specific kernel implementation.
Future features may introduce new regions or interrupt entries
(VGA may add legacy ranges, AER might add an IRQ for error
signalling).  Fix this before it gets us into trouble.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Cc: qemu-stable@nongnu.org

hw/vfio_pci.c

@@ -1837,13 +1837,13 @@ static int vfio_get_device(VFIOGroup *group, const char *name, VFIODevice *vdev)
         error_report("Warning, device %s does not support reset\n", name);
     }
 
-    if (dev_info.num_regions != VFIO_PCI_NUM_REGIONS) {
+    if (dev_info.num_regions < VFIO_PCI_CONFIG_REGION_INDEX + 1) {
         error_report("vfio: unexpected number of io regions %u\n",
                      dev_info.num_regions);
         goto error;
     }
 
-    if (dev_info.num_irqs != VFIO_PCI_NUM_IRQS) {
+    if (dev_info.num_irqs < VFIO_PCI_MSIX_IRQ_INDEX + 1) {
         error_report("vfio: unexpected number of irqs %u\n", dev_info.num_irqs);
         goto error;
     }