qemu.tests.cfg: Update qemu guest agent config

Signed-off-by: Qingtang Zhou <qzhou@redhat.com>
qemu.tests: Fix module import problem in qemu_guest_agent_snapshot test

Signed-off-by: Qingtang Zhou <qzhou@redhat.com>
qemu.tests.qemu_guest_agent: Update fsfreeze/fsthaw workflow

The original flow of freeze/thaw testing will make autotest
hang when rebooting/shutdown guest after freeze guest fs.
This patch moves guest reboot/shutdown operation after guest
is thawed.

Signed-off-by: Qingtang Zhou <qzhou@redhat.com>
virt.guest_agent: Remove qemu monitor operation from this module

This module should not depend on qemu monitor interfaces.

Signed-off-by: Qingtang Zhou <qzhou@redhat.com>
virt.guest_agent: Remove vm related operation in this module

Signed-off-by: Qingtang Zhou <qzhou@redhat.com>
virt.guest_agent: Update vm name arguments in exception classes

Signed-off-by: Qingtang Zhou <qzhou@redhat.com>
virt.guest_agent: Define constant for guest agent serial type

Signed-off-by: Qingtang Zhou <qzhou@redhat.com>
virt.guest_agent: Remove VAgentNotSupportedSerialError

Signed-off-by: Qingtang Zhou <qzhou@redhat.com>
qemu.tests.qemu_guest_agent: Update QemuAgent initiation code

Signed-off-by: Qingtang Zhou <qzhou@redhat.com>
qemu.tests.qemu_guest_agent: Fix test error message

Signed-off-by: Qingtang Zhou <qzhou@redhat.com>
virt.qemu_vm: Seperate qemu monitor creation code from vm.create()

Signed-off-by: Qingtang Zhou <qzhou@redhat.com>
virt.qemu_monitor: Store qemu VM object in monitor object

Signed-off-by: Qingtang Zhou <qzhou@redhat.com>
virt.env_process: Close monitor socket after test

The socket connection is alive when a test finishes, normally it works
well. But there is one situation that the next test case will try to
re-connect to these monitor socket after unpickled from env file, even
though the former connection is still established.

In this situation auotest will report a error of "Could not find (qemu)
prompt", but the monitor works well in fact. To avoid this problem, this
patch just close all the monitor socket connections at the end of a test
case, and the following test case will try to re-connect if needed.

Signed-off-by: Qingtang Zhou <qzhou@redhat.com>