tests: qemumonitorjson: Add long backing chain test case for node name detection

tests/qemumonitorjsondata/qemumonitorjson-nodename-2.result

+filename    : '/var/lib/libvirt/images/rhel7.3.1484071880'
+format node : '#block161'
+storage node: '#block013'
+backingfile : '/var/lib/libvirt/images/rhel7.3.1484071877'
+backing ptr : '#block316'
+  filename    : '/var/lib/libvirt/images/rhel7.3.1484071877'
+  format node : '#block316'
+  storage node: '#block248'
+  backingfile : '/var/lib/libvirt/images/rhel7.3.1484071876'
+  backing ptr : '#block560'
+    filename    : '/var/lib/libvirt/images/rhel7.3.1484071876'
+    format node : '#block560'
+    storage node: '#block430'
+    backingfile : '/var/lib/libvirt/images/rhel7.3.1484071872'
+    backing ptr : '#block717'
+      filename    : '/var/lib/libvirt/images/rhel7.3.1484071872'
+      format node : '#block717'
+      storage node: '#block612'
+      backingfile : '/var/lib/libvirt/images/rhel7.3.1483615252'
+      backing ptr : '#block998'
+        filename    : '/var/lib/libvirt/images/rhel7.3.1483615252'
+        format node : '#block998'
+        storage node: '#block843'
+        backingfile : '/var/lib/libvirt/images/rhel7.3.1483605924'
+        backing ptr : '#block1119'
+          filename    : '/var/lib/libvirt/images/rhel7.3.1483605924'
+          format node : '#block1119'
+          storage node: '#block1075'
+          backingfile : '/var/lib/libvirt/images/rhel7.3.1483605920'
+          backing ptr : '#block1350'
+            filename    : '/var/lib/libvirt/images/rhel7.3.1483605920'
+            format node : '#block1350'
+            storage node: '#block1204'
+            backingfile : '/var/lib/libvirt/images/rhel7.3.1483546244'
+            backing ptr : '#block1528'
+              filename    : '/var/lib/libvirt/images/rhel7.3.1483546244'
+              format node : '#block1528'
+              storage node: '#block1427'
+              backingfile : '/var/lib/libvirt/images/rhel7.3.1483545901'
+              backing ptr : '#block1799'
+                filename    : '/var/lib/libvirt/images/rhel7.3.1483545901'
+                format node : '#block1799'
+                storage node: '#block1690'
+                backingfile : '/var/lib/libvirt/images/rhel7.3.1483545313'
+                backing ptr : '#block1979'
+                  filename    : '/var/lib/libvirt/images/rhel7.3.1483545313'
+                  format node : '#block1979'
+                  storage node: '#block1814'
+                  backingfile : '/var/lib/libvirt/images/rhel7.3.1483536402'
+                  backing ptr : '#block2157'
+                    filename    : '/var/lib/libvirt/images/rhel7.3.1483536402'
+                    format node : '#block2157'
+                    storage node: '#block2008'
+                    backingfile : '/var/lib/libvirt/images/rhel7.3.qcow2'
+                    backing ptr : '#block2399'
+                      filename    : '/var/lib/libvirt/images/rhel7.3.qcow2'
+                      format node : '#block2399'
+                      storage node: '#block2281'
+                      backingfile : '<null>'
+                      backing ptr : '<null>'

tests/qemumonitorjsontest.c

@@ -2929,6 +2929,7 @@ mymain(void)
     } while (0)
 
     DO_TEST_BLOCK_NODE_DETECT("1", "#block118");
+    DO_TEST_BLOCK_NODE_DETECT("2", "#block161");
 
 #undef DO_TEST_BLOCK_NODE_DETECT