drm/amd/display: Underflow Seen on DCN401 eGPU

drm/amd/display: Underflow Seen on DCN401 eGPU

[WHY]
In dcn401 we read clock values before FW is loaded. These incorrect
values cause the driver to believe that we are running higher clocks
than what we actually have. This then causes corruption/underflow for
the eGPU.

[HOW]
When new values are read from HW, update internal structures to
propagate the new/correct value. Fixes issue

Signed-off-by: Daniel Sa <Daniel.Sa@amd.com>
Reviewed-by: Alvin Lee <alvin.lee2@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Rodrigo Siqueira <rodrigo.siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>