ASoC: rt5645: cleanup DMI matching code

Rather then doing a dmi_check_system() per possible system use an array
with all known systems, with dmi_system_id.driver_data pointing to the
platform-data for the matching system.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mark Brown <broonie@kernel.org>