[Why]
DPIA traces from DMUB is not enabled by default, which is
less convenient to debug DPIA related issues because we have
to resort to other debug tools to enable DPIA trace.

[How]
Exposes interfaces to update trace mask from the DMUB GPINT commands.
Also provides DC implementations to enable DPIA trace.
Reviewed-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Acked-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Stylon Wang <stylon.wang@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>