drm/amd/display: implement DPMS DTN test v2

[why]
Existing DTN infrastructure in driver is hacky.  It uses implicit log
names, and also incorrect escape ID.

[how]
- Implement using generic DTN escape ID.
- Move file logging functionality from driver to to script; driver now outputs to string/buffer
- Move HWSS debug functionality to separate c file
- Add debug functionalty for per-block logging as CSV
- Add pretty print in python

Signed-off-by: Jun Lei <Jun.Lei@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>