[Sound-open-firmware] Initial support for i.MX8 platform

Hi Liam / Pierre,

I've sent initial patches for i.MX8 FW [1]. There are still a lot of things to be done but I will to solve them step by step.

Appreciate any review and hope to get at least the basic support accepted then build on top of that.

Next steps:

1) Add CI support to compile for imx architecture (both FW/Linux) 2) Send Linux kernel side patches.

Can you guide me on how to deal with 1)?

thanks, Daniel.

[1] https://github.com/thesofproject/sof/pull/1457