[TF-M] [RFC] [Source Structure] Design document is availiable.

Hi,

There is an upcoming source structure adjustment for TF-M. The basic idea is to make the structure simple and easy to be understood by users. The significant change would be a long term goal so no worry. In the beginning, there would be changes in core and platform to align with HAL changes.

Please help to put comments on the design documents - after aligned, this document would be a user guide document to describe the source structure of TF-M.

The patch is here: https://review.trustedfirmware.org/c/trusted-firmware-m/+/4112

And the issue link: https://developer.trustedfirmware.org/T751

Feel free to put any comments or ask questions.

Thanks.

/Ken