The commit 89563efc fix the
monitor error when closing the QEMU monitor. The QEMU agent
has a problem similar to QEMU monitor. So fix the QEMU agent
with the same method.
Signed-off-by: NWang Yechao <wang.yechao255@zte.com.cn>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>