qemuagenttest: Fix checking of shutdown mode

Coverity complained about unused variable that contains the shutdown
mode. The original intention was to check it against the requested mode.

Also the fixed check revealed a mistake in the expected shutdown mode.

Reported by John Ferlan.

tests/qemuagenttest.c

@@ -251,6 +251,13 @@ qemuAgentShutdownTestMonitorHandler(qemuMonitorTestPtr test,
         goto cleanup;
     }
 
+    if (STRNEQ(mode, data->mode)) {
+        ret = qemuMonitorReportError(test,
+                                     "expected shutdown mode '%s' got '%s'",
+                                     data->mode, mode);
+        goto cleanup;
+    }
+
     /* now don't reply but return a qemu agent event */
     qemuAgentNotifyEvent(qemuMonitorTestGetAgent(test),
                          data->event);
@@ -279,7 +286,7 @@ testQemuAgentShutdown(const void *data)
         goto cleanup;
 
     priv.event = QEMU_AGENT_EVENT_SHUTDOWN;
-    priv.mode = "shutdown";
+    priv.mode = "halt";
 
     if (qemuMonitorTestAddHandler(test, qemuAgentShutdownTestMonitorHandler,
                                   &priv, NULL) < 0)