qemu: fix argument of virDomainNetGetActualDirectMode

it should be a comparison of modes between new and old devices. So
the argument of the second virDomainNetGetActualDirectMode should be
newdev.
Signed-off-by: NZhiPeng Lu <lu.zhipeng@zte.com.cn>
(cherry picked from commit c77bc47f)

src/qemu/qemu_hotplug.c

@@ -3273,7 +3273,7 @@ qemuDomainChangeNet(virQEMUDriverPtr driver,
 
     if (STRNEQ_NULLABLE(virDomainNetGetActualDirectDev(olddev),
                         virDomainNetGetActualDirectDev(newdev)) ||
-        virDomainNetGetActualDirectMode(olddev) != virDomainNetGetActualDirectMode(olddev) ||
+        virDomainNetGetActualDirectMode(olddev) != virDomainNetGetActualDirectMode(newdev) ||
         !virNetDevVPortProfileEqual(virDomainNetGetActualVirtPortProfile(olddev),
                                     virDomainNetGetActualVirtPortProfile(newdev)) ||
         !virNetDevVlanEqual(virDomainNetGetActualVlan(olddev),