virttest.qemu_devices: Use qid for hotplug verification

Proper identification in qemu_devices is object.get_qid().

Signed-off-by: Lukáš Doktor <ldoktor@redhat.com>
qemu.tests.virtio_console: Update test_hotplug_virtio_pci

Fix the problem with duplicated IDs caused by early device_del execution.
Monitor returns no output but internally waits for OS ACPI respone. This
message, in case kernel is not yet initialized, never occurs.

This version resends the device_del in the first round until it succeeds,
than it just waits until the device disappears.

Additionally the test was rewritten to use qemu_devices to handle the
hotplug/unplug and the test cfg was tweaked to be more intensive.

Signed-off-by: Lukáš Doktor <ldoktor@redhat.com>
Merge pull request #1206 from ldoktor/virtio_console

qemu.tests.virtio_console: Update test_hotplug_virtio_pci
PEP8 mass auto fix

Catching up with some problems found w.r.t. coding style

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
Merge pull request #1208 from autotest/pep8-fix

PEP8 mass auto fix
virsh_start: Need to ensure stopped before run

When run after virsh.shutdown, the first virsh.start was failing with
because the domain was already started.  Adjusted the .cfg file to
ensure setting of the 'kill_vm_before_test' in the status_error_no
variant.

Also, changed the error returned from using 'stdout' to 'stderr' so that
"Domain is already active" would be displayed.