mfd: Add support for COMe-bHL6 and COMe-cTH6 to Kontron PLD driver

This patch adds DMI system IDs for the new Kontron modules COMe-bHL6 and
COMe-cTH6 to the Kontron PLD driver.

Acked-by: Kevin Strasser <strassek@engr.orst.edu>
Signed-off-by: Michael Brunner <michael.brunner@kontron.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>