Support Cirrus Logic CS42L42 headphone codec

[brentlu]

It's a series to:

1. Add a machine driver, sof_cs42l42, to support Cirrus Logic CS42L42 + Maxim MAX98357A on GLK devices.
2. Move MAX98357A support to a common module, sof_maxim_common
3. Code refactory to sof_rt5682 and sof_cs42l42 to use sof_maxim_common to support Maxim MAX98357A