SoC: SOF: Intel: hda/mtl: Improve and enable DMI L1

Merge series from Peter Ujfalusi <peter.ujfalusi@linux.intel.com>:

The first patch will improve the managing of DMI L1 by tracking it's
enabled/disabled state to avoid unconditional changes to it's state.

The remaining two patch will enable the DMI L1 for MTL platforms (ACE 1.0)