ASoC: Intel: add support for ALC3270 codec

Use ACPI ID 10EC3270 to load machine driver for cht-bsw-rt5645
and add reference to 3270 to use the rt5645 mode

Tested on Asus T100HA

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