ASoC: Intel: Atom: add support for CHT w/ RT5640

Some CHT-T platforms make use of the Realtek RT5640 codec. Make use
of the machine driver developed for Baytrail.

Tested on Tronsmart Ara X5.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>