This is a bit easier to use than "-trace" if you are also enabling
other kinds of logging.  It is also more discoverable for experienced
QEMU users, and accessible from user-mode emulators.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-id: 1452174932-28657-12-git-send-email-den@openvz.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>