[Why & How]
Extend existing support for DCN2.1 DMUB diagnostic logging to
DCN3.1 so we can collect useful information if the DMUB hangs.
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Reviewed-by: Harry Wentland <harry.wentland@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>