Merge pull request #521 from PandaWei/aexpect

pci_hotplug: replace virttest.aexpect with aexpect

qemu/tests/pci_hotplug.py

 import re
 import logging
 import string
+import aexpect
 
 from autotest.client.shared import error
 
-from virttest import aexpect
 from virttest import utils_misc
 from virttest import storage
 from virttest import utils_test