qemu: Fix memory leak in qemuDomainUpdateMemoryDeviceInfo

The @meminfo allocated in qemuMonitorGetMemoryDeviceInfo() may be
lost when qemuDomainObjExitMonitor() failed.
Signed-off-by: NYi Wang <wang.yi59@zte.com.cn>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

src/qemu/qemu_domain.c

@@ -5767,8 +5767,10 @@ qemuDomainUpdateMemoryDeviceInfo(virQEMUDriverPtr driver,
 
     rc = qemuMonitorGetMemoryDeviceInfo(priv->mon, &meminfo);
 
-    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+    if (qemuDomainObjExitMonitor(driver, vm) < 0) {
+        virHashFree(meminfo);
         return -1;
+    }
 
     /* if qemu doesn't support the info request, just carry on */
     if (rc == -2)