qemu.tests.cfg: Enable qemu_guest_agent tests on newer Fedora host

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