Add USB ID 0413:6a04 for Leadtek WinFast DTV2000DS.

Thanks to Gavin Ramm <gavin_ramm@hotmail.com> for reporting this.
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>