The migration tests are currently broken for an aarch64 host because
the tests pass no 'machine' and 'cpu' options on the QEMU command
line.
Add a separate class to each architecture so that we can specify
'machine' and 'cpu' options instead of relying on defaults.
Add a skip decorator to keep the current behavior of only running
migration tests when the qemu target matches the host architecture.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
8049df7cee