interface: opendous_ftdi config file added

This config file add support to the opendous cable based on the chip ft2232H,
using the ftdi interface driver.

Change-Id: I4491f99d7b14f7078a04583ef0c4acd8692c4349
Signed-off-by: Rodrigo Melo <rmelo@inti.gob.ar>
Reviewed-on: http://openocd.zylin.com/1097
Tested-by: jenkins
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>