Merge remote-tracking branch 'remotes/cohuck/tags/s390x-20160808' int…

…o staging

One more s390x fix for a bug in the pci rework.

# gpg: Signature made Mon 08 Aug 2016 11:49:34 BST
# gpg:                using RSA key 0xDECF6B93C6F02FAF
# gpg: Good signature from "Cornelia Huck <huckc@linux.vnet.ibm.com>"
# gpg:                 aka "Cornelia Huck <cornelia.huck@de.ibm.com>"
# Primary key fingerprint: C3D0 D66D C362 4FF6 A8C0  18CE DECF 6B93 C6F0 2FAF

* remotes/cohuck/tags/s390x-20160808:
  s390x/pci: fix null pointer bug

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/s390x/s390-pci-bus.c

@@ -712,7 +712,7 @@ static void s390_pcihost_hot_unplug(HotplugHandler *hotplug_dev,
         pci_dev = PCI_DEVICE(dev);
 
         for (i = 0 ; i < PCI_SLOT_MAX; i++) {
-            if (s->pbdev[i]->pdev == pci_dev) {
+            if (s->pbdev[i] && s->pbdev[i]->pdev == pci_dev) {
                 pbdev = s->pbdev[i];
                 break;
             }