drm/amd/display: Disable Z8 minimum stutter period check for DCN35

[Why]
The threshold is no longer useful for blocking suboptimal power states
for DCN35 based on real measurement.

[How]
Reduce to the minimum threshold duration, 1us.

Reviewed-by: Gabe Teeger <gabe.teeger@amd.com>
Acked-by: Roman Li <roman.li@amd.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>