linux-imx

ASoC: fsl: Add generic DAI driver

On i.MX8 platforms that have a DSP the DAI handling is taken care
of by two entities:
	* Application Processor (AP), which runs Linux
	* DSP, which runs a firmware (typically Sound Open Firmware)

The DSP has access to DAI IP registers, but it cannot easily handle
resources like:
	* clock
	* power domain management
	* pinctrl.

For this reason we introduce a generic FSL DAI driver which will take
care of the resources above.

Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>