migration: Add co-maintainers for migration

migration: Add co-maintainers for migration

Per the qemu upstream call a few hours ago, proposing Fabiano and myself as
the co-maintainer for migration subsystem to help Juan.

Cc: Fabiano Rosas <farosas@suse.de>
Cc: Juan Quintela <quintela@redhat.com>
Acked-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231003143847.9245-1-peterx@redhat.com>