hw/ppc/spapr_pci: Do not create DT for disabled PCI device

Disabled means it is a disabled SR-IOV VF and hidden from the guest.
Do not create DT when starting the system and also keep the disabled PCI
device not linked to DRC, which generates DT in case of hotplug.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Shivaprasad G Bhat<sbhat@linux.ibm.com>
Tested-by: Shivaprasad G Bhat<sbhat@linux.ibm.com>
Message-Id: <20250116-reuse-v20-1-7cb370606368@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

hw/ppc/spapr_pci.c

@@ -1283,8 +1283,7 @@ static void spapr_dt_pci_device_cb(PCIBus *bus, PCIDevice *pdev,
     PciWalkFdt *p = opaque;
     int err;
 
-    if (p->err) {
-        /* Something's already broken, don't keep going */
+    if (p->err || !pdev->enabled) {
         return;
     }
 
@@ -1572,6 +1571,14 @@ static void spapr_pci_plug(HotplugHandler *plug_handler,
     SpaprDrc *drc = drc_from_dev(phb, pdev);
     uint32_t slotnr = PCI_SLOT(pdev->devfn);
 
+    /*
+     * If DR or the PCI device is disabled we don't need to do anything
+     * in the case of hotplug or coldplug callbacks.
+     */
+    if (!pdev->enabled) {
+        return;
+    }
+
     g_assert(drc);
 
     if (IS_PCI_BRIDGE(plugged_dev)) {
@@ -1647,6 +1654,11 @@ static void spapr_pci_unplug_request(HotplugHandler *plug_handler,
     SpaprDrc *drc = drc_from_dev(phb, pdev);
 
     g_assert(drc);
+
+    if (!drc->dev) {
+        return;
+    }
+
     g_assert(drc->dev == plugged_dev);
 
     if (!spapr_drc_unplug_requested(drc)) {