Add the PowerQUICC audio support using the QMC

Merge series from Herve Codina <herve.codina@bootlin.com>:

This series adds support for audio using the QMC controller available in
some Freescale PowerQUICC SoCs.

This series contains three parts in order to show the different blocks
hierarchy and their usage in this support.

The first one is related to TSA (Time Slot Assigner).
The TSA handles the data present at the pin level (TDM with up to 64
time slots) and dispatchs them to one or more serial controller (SCC).

The second is related to QMC (QUICC Multichannel Controller).
The QMC handles the data at the serial controller (SCC) level and splits
again the data to creates some virtual channels.

The last one is related to the audio component (QMC audio).
It is the glue between the QMC controller and the ASoC component. It
handles one or more QMC virtual channels and creates one DAI per QMC
virtual channels handled.