Add support for Leon touch devices, which is the same as
falco/peppy/wolf on the same buses using the LynxPoint-LP I2C
via the i2c-designware-pci driver.

Based on these patches from the chromeos-3.8 kernel:
https://chromium-review.googlesource.com/168351
https://chromium-review.googlesource.com/173445



Signed-off-by: Gene Chen <gene.chen@intel.com>
Signed-off-by: Benson Leung <bleung@chromium.org>
Tested-by: Scot Doyle <lkml14@scotdoyle.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Olof Johansson <olof@lixom.net>